The ability of wheat to adapt to a wide range of environmental conditions is determined mostly by allelic diversity among genes regulating vernalization requirement.Vrn-1 is a major regulator of this requirement.In th...The ability of wheat to adapt to a wide range of environmental conditions is determined mostly by allelic diversity among genes regulating vernalization requirement.Vrn-1 is a major regulator of this requirement.In this study,two novel alleles of Vrn-A1 were discovered in Chinese cultivars:vrn-A1n was identified in two landraces,Jiunong 2 and Ganchun 16,and Vrn-A1o was detected in Duanhongmangmai.Both novel alleles showed a linked duplication in the promoter region.The common copy of these two alleles was identical to the recessive allele vrn-A1.Compared with the recessive allele vrn-A1,the other copy of vrn-A1n contained a 54-bp deletion in the promoter region and the distinct copy of Vrn-A1o contained an11-bp deletion in the promoter region.In segregating populations in the greenhouse under nonvernalizing(20–25°C)and long-day(16 h light)conditions,plants with the novel vrn-A1n allele did not head earlier than those with the recessive vrn-A1 allele.However,plants that were either homozygous or heterozygous for the novel Vrn-A1o allele headed earlier than those with the recessive vrn-A1 allele.To identify the novel allele with the small-sized product and facilitate screening,a DNA marker for the novel dominant allele Vrn-A1o was designed.Analysis of the novel-allele distribution showed that two cultivars carrying the vrn-A1n allele were dispersed in the northwestern spring wheat zone,and 12 cultivars carrying the dominant Vrn-A1o allele were widely distributed in the northwestern spring wheat zone,Xinjiang winter and spring wheat zone,Yellow and Huai River valley winter wheat zone,and QinghaiTibetan Plateau spring and winter wheat zone.Our study identifies useful germplasm and a DNA marker for wheat breeding.展开更多
Genetic diversity at Gli_1, Gli_2 and Glu_1 loci was investigated in 89 Sichuan wheat (Triticum aestivum L.) landraces by using acid polyacrylamide gel electrophoresis (APAGE) and SDS_PAGE. In these landraces, a total...Genetic diversity at Gli_1, Gli_2 and Glu_1 loci was investigated in 89 Sichuan wheat (Triticum aestivum L.) landraces by using acid polyacrylamide gel electrophoresis (APAGE) and SDS_PAGE. In these landraces, a total of 32 gliadin and 3 high_molecular_weight (HMW) glutenin patterns were observed. In total, 14, 15 and 5 alleles were identified at Gli_1, Gli_2 and Glu_1, respectively. At each locus, the alleles in higher frequency were Gli_A1a (89%), Gli_B1h (46%), Gli_D1a (65%), Gli_A2a (64%), Gli_B2j (45%), Gli_D2a (48%), Glu_A1c (99%), Glu_B1b (99%) and Glu_D1a (100%). The Nei's genetic variation index (H) of Sichuan wheat landraces was 0.370?6, varying from 0 to 0.708?7. The highest genetic diversity was found at Gli_B2 locus, while the lowest was found at Glu_D1. The genetic diversity at Gli loci was higher than that of Glu_1 loci among these landraces, but it was much lower than that of modern wheat cultivars. These results indicated a narrow genetic base of Sichuan wheat landraces. In this study, “Chengdu_guangtou” had the identical gliadin and HMW_glutenin patterns with “Chinese Spring”, further supporting the proposal that “Chinese Spring” is a strain of “Chengdu_guangtou”.展开更多
Genetic diversity at Gli_1, Gli_2 and Glu_1 loci was investigated in 32 accessions of Chinese endemic wheat by using acid polyacrylamide gel electrophoresis (APAGE) and sodium dodecyl sulfate (SDS)_PAGE. There were 8 ...Genetic diversity at Gli_1, Gli_2 and Glu_1 loci was investigated in 32 accessions of Chinese endemic wheat by using acid polyacrylamide gel electrophoresis (APAGE) and sodium dodecyl sulfate (SDS)_PAGE. There were 8 gliadin and 3 high_molecular_weight (HMW)_glutenin patterns in 14 Yunnan hulled wheat ( Triticum aestivum ssp. yunnanese King) accessions, 9 gliadin and 4 HMW_glutenin patterns in 9 Tibetan weedrace ( T. aestivum ssp. tibetanum Shao ) accessions, and 9 gliadin and 5 HMW_glutenin patterns in 9 Xinjiang rice wheat ( T. petropavlovskyi Udacz. et Migusch.) accessions. One accession (i.e. Daomai 2) carried new subunits 2.1+10.1 encoded by Glu_D1. Among the three Chinese endemic wheat groups, a total of 10, 14 and 11 alleles at Gli_1 locus; 11, 14 and 12 alleles at Gli_2 locus; and 5, 6 and 8 alleles at Glu_1 locus were identified, respectively. Among Yunnan hulled wheat, Tibetan weedrace and Xinjiang rice wheat, the Nei's genetic variation indexes were 0.3798, 0.5625 and 0.5693, respectively. These results suggested that Tibetan weedrace and Xinjiang rice wheat had higher genetic diversity than Yunnan hulled wheat.展开更多
This paper studies the offspring＇s genotype frequency of the selfing population on multiple alleles with limited loci.A recursive algorithm is given for it.It is discovered that the genotype frequency of homozygous g...This paper studies the offspring＇s genotype frequency of the selfing population on multiple alleles with limited loci.A recursive algorithm is given for it.It is discovered that the genotype frequency of homozygous gene of limited loci increases by generations.Relative increment reduces by generations and the genotype frequency tends to a definite value finally.The genotype frequency of limited loci with hybrid gene tends to 0 finally.But it is possibility that the genotype frequency increases in previous generations then reduces later.It is found that the number of the hybrid gene are more,the speeds tending to 0 are quicker.展开更多
Genetic polymorphism of the major histocompatibility complex （MHC） B-LBⅡ gene was studied by amplification of exon 2 using PCR, followed by cloning and DNA sequencing in eight indigenous Chinese chicken populations...Genetic polymorphism of the major histocompatibility complex （MHC） B-LBⅡ gene was studied by amplification of exon 2 using PCR, followed by cloning and DNA sequencing in eight indigenous Chinese chicken populations. To reveal the genetic variation of the B-LB Ⅱ gene, 37 types of patterns detected by PCR-SSCP were investigated first, which would be used to screen novel B-LB Ⅱsequences within the breeds. The types of PCR-SSCP patterns and final sequencing allowed for the identification of 31 novel MHC B-LBⅡ alleles from 30 unrelated individuals of Chinese chickens that were sampled. These are the first designators for the alleles of chicken MHC B-LBⅡ gene based on the rule of assignment for novel mammalian alleles. Sequence alignment of the 31 B-LB Ⅱ alleles revealed a total of 68 variable sites in the fragment of exon 2, of which 51 parsimony informative and 17 singleton variable sites were observed. Among the polymorphic sites, the nucleotide substitutions in the first and second positions of the codons accounted for 36.76% and 35.29%, respectively. The sequence similarities between the alleles were estimated to be 90.6%-99.5%. The relative frequencies of synonymous and nonsynonymous nucleotide substitutions within the region were 2.92%±0.94% and 14.64%±2.67%, respectively. These results indicated that the genetic variation within exon 2 appeared to have largely arisen by gene recombination and balancing selection. Alignment of the deduced amino acid sequences of the β1 domain coded by exon 2 revealed 6 synonymous mutations and 27 nonsynonymous substitutions at the 33 disparate sites. In particular, the nonsynonymous substitutions at the putative peptide-binding sites are considered to be associated with immunological specificity of MHC B-LB Ⅱ molecule in Chinese native chickens. These results can provide a molecular biological basis for the study of disease resistance in chicken breeding.展开更多
AIM. To investigate the influence of HLA-DRB1 alleles and HBV genotypes on inberferon-α therapy for chronic hepatitis B. METHODS： HLA-DRBI＊03, ＊07, ＊09,＊12, ＊15 alleles were determined using polymerase chain re...AIM. To investigate the influence of HLA-DRB1 alleles and HBV genotypes on inberferon-α therapy for chronic hepatitis B. METHODS： HLA-DRBI＊03, ＊07, ＊09,＊12, ＊15 alleles were determined using polymerase chain reaction/sequence specific primer （PCR/SSP） technique in 126 patients with chronic hepatitis B and 76 normal control subjects in Shandong Province, and HBV genotypes were determined by nested-PCR analysis using type-specific primers in 126 patients. RESULTS： The positivity of HLA-DRB1＊07 allele in chronic hepatitis B group was significantly higher than that in normal control group （X^2 = 6.33, P〈0.025, RR = 2.37）. Among the 126 patients, genotype B was found in 38 （30.2%）, genotype C in 69 （54.8%）, and mixed genotype （B＋C） in 19 （15.0%）, genotypes D-F were not found. Among the 46 DRB1＊07（＋） patients, 7 were responders and 39 were non-responders among them （X^2 = 6.71, P〈0.05）. The positivity of HLADRB1＊07 and prevalence of HBV genotype C were significantly higher in non-responders than in responders. CONCLUSION： High positivities of HLA-DRB1 ＊07 allele and HBV genotype C are closely associated with the lower response to interferon-α therapy for chronic hepatitis B.展开更多
Objective To determine the distribution of HLA-B alleles in the Chinese Yi ethnic group and its association with HIV infection. Methods One hundred and six unrelated healthy HIV negative and 73 HIV positive Chinese Yi...Objective To determine the distribution of HLA-B alleles in the Chinese Yi ethnic group and its association with HIV infection. Methods One hundred and six unrelated healthy HIV negative and 73 HIV positive Chinese Yi ethnic individuals were typed by PCR-SSP. Results The frequency of alleles B*07, B*35, and B*46 were increased in HTV-1 -positive subjects, whereas the alleles B*55, B*44 and B*78 were absent in the HIV-infected persons studied. The B*46 allele was present in a significantly higher gene frequency among HIV-1-positive individuals (P=0.02, OR=3.32, 95% CI=1.13-9.78) compared with control subjects. Conclusion HLA-B*46 may be associated with its susceptibility to HIV-1 infections.展开更多
Chrysanthemums are sensitive to waterlogging stress,and the development of screening methods for tolerant germplasms or genes and the breeding of tolerant new varieties are of great importance in chrysanthemum breedin...Chrysanthemums are sensitive to waterlogging stress,and the development of screening methods for tolerant germplasms or genes and the breeding of tolerant new varieties are of great importance in chrysanthemum breeding.To understand the genetic basis of waterlogging tolerance(WT)in chrysanthemums,we performed a genome-wide association study(GWAS)using 92,811 single nucleotide polymorphisms(SNPs)in a panel of 88 chrysanthemum accessions,including 64 spray cut and 24 disbud chrysanthemums.The results showed that the average MFVW(membership function value of waterlogging)of the disbud type(0.65)was significantly higher than that of the spray type(0.55)at P<0.05,and the MFVW of the Asian accessions(0.65)was significantly higher than that of the European accessions(0.48)at P<0.01.The GWAS performed using the general linear model(GLM)and mixed linear model(MLM)identified 137 and 14 SNP loci related to WT,respectively,and 11 associations were commonly predicted.By calculating the phenotypic effect values for 11 common SNP loci,six highly favorable SNP alleles that explained 12.85—21.85%of the phenotypic variations were identified.Furthermore,the dosage-pyramiding effects of the favorable alleles and the significant linear correlations between the numbers of highly favorable alleles and phenotypic values were identified(r2=0.45;P<0.01).A major SNP locus(Marker6619-75)was converted into a derived cleaved amplified polymorphic sequence(dCAPS)marker that cosegregated with WT with an average efficiency of 78.9%.Finally,four putative candidate genes in the WT were identified via quantitative real-time PCR(qRT-PCR).The results presented in this study provide insights for further research on WT mechanisms and the application of molecular marker-assisted selection(MAS)in chrysanthemum WT breeding programs.展开更多
AIM:To evaluate the association of human leukocyte antigen(HLA)-DQB1 alleles with hepatocellular carcinoma(HCC) through meta-analysis of published data.METHODS:Case-control studies on HLA-DQB1 allele association with ...AIM:To evaluate the association of human leukocyte antigen(HLA)-DQB1 alleles with hepatocellular carcinoma(HCC) through meta-analysis of published data.METHODS:Case-control studies on HLA-DQB1 allele association with HCC published up to January 2010 were included in the analyses.The odds ratios(ORs) of HLADQB1 allele distributions in HCC patients were analyzed and compared with healthy controls.The meta-analysis software REVMAN 5.0 was applied for investigating heterogeneity among individual studies and for summarizing all the studies.A meta-analysis was performed using fixed-effect or random-effect methods,depending on the absence or presence of significant heterogeneity.Seven case-control studies containing 398 cases and 594 controls were included in the final analysis.RESULTS:Among the five family alleles,two(DQB1*02 and DQB1*03) were found to be significantly associated with the risk of HCC.The combined OR for the association of DQB1*02 and DQB1*03 allele with the risk for HCC was 1.78(95% CI:1.05-3.03,P = 0.03) and 0.65(95% CI:0.48-0.89,P = 0.007),respectively.Among the 13 specific alleles,two(DQB1*0502 and DQB1*0602) were significantly associated with risk of HCC.The combined OR for the association of DQB1*0502 and DQB1*0602 allele with the risk for HCC was 1.82(95% CI:1.14-2.92,P = 0.01) and 0.58(95% CI:0.36-0.95,P = 0.03),respectively.No significant association was established for other HLA-DQB1 family alleles and specific alleles.CONCLUSION:Our results support the hypothesis that specific HLA-DQB1 allele families and alleles might influence the susceptibility or resistance to HCC,although it needs further investigations.展开更多
Self-incompatibility(SI)to self-compatibility(SC)transition is one of the most frequent and prevalent evolutionary shifts in flowering plants.Prunus L.(Rosaceae)is a genus of over 200 species most of which exhibit a G...Self-incompatibility(SI)to self-compatibility(SC)transition is one of the most frequent and prevalent evolutionary shifts in flowering plants.Prunus L.(Rosaceae)is a genus of over 200 species most of which exhibit a Gametophytic SI system.Peach[Prunus persica(L.)Batsch;2n=16]is one of the few exceptions in the genus known to be a fully selfcompatible species.However,the evolutionary process of the complete and irreversible loss of SI in peach is not well understood and,in order to fill that gap,in this study 24 peach accessions were analyzed.Pollen tube growth was controlled in self-pollinated flowers to verify their self-compatible phenotypes.The linkage disequilibrium association between alleles at the S-locus and linked markers at the end of the sixth linkage group was not significant(P>0.05),except with the closest markers suggesting the absence of a signature of negative frequency dependent selection at the S-locus.Analysis of SFB1 and SFB2 protein sequences allowed identifying the absence of some variable and hypervariable domains and the presence of additionalα-helices at the C-termini.Molecular and evolutionary analysis of SFB nucleotide sequences showed a signature of purifying selection in SFB2,while the SFB1 seemed to evolve neutrally.Thus,our results show that the SFB2 allele diversified after P.persica and P.dulcis(almond)divergence,a period which is characterized by an important bottleneck,while SFB1 diversified at a transition time between the bottleneck and population expansion.展开更多
The potential impact of human leukocyte antigen （HLA） genotype variations on development of diabetic peripheral neuropathy （DPN） is not well determined. This study aimed to identify the association of HLA class II...The potential impact of human leukocyte antigen （HLA） genotype variations on development of diabetic peripheral neuropathy （DPN） is not well determined. This study aimed to identify the association of HLA class II alleles with DPN in type 2 diabetes （T2D） patients. Totally 106 T2D patients, 49 with DPN and 57 without DPN, and 100 ethnic-matched healthy controls were analyzed. Both groups of the patients were matched based on sex, age, body mass index （BMI） and duration of T2D. Polyneuropathy was diagnosed using electrodiagnostic methods. HLA-DRB1 and DQB1 genotyping was performed in all subjects by the polymerase chain reaction with sequence-specific primers （PCR-SSP） method. T2D patients with DPN showed higher frequencies of HLA-DRB1＊10 and DRB1＊12 alleles compared to control group （P = 0.04）. HLA-DQB1＊02 allele and HLA-DRB1＊07-DQB1＊02 haplotype were associated with a decreased risk for developing DPN in T2D patients （P = 0.02 and P = 0.05 respectively）. Also, patients with severe neuropathy showed higher frequencies of DRB1＊07 （P = 0.003） and DQB1＊02 （P = 0.02） alleles than those with mild-to-moderate form of neuropathy. The distribution of DRB 1 and DQB 1 alleles and haplotypes were not statistically different between all patients and healthy controls. Our findings implicate a possible protective role of HLA-DQB1＊02 allele and HLA-DRB1＊07-DQB1＊02 haplotype against development of peripheral neuropathy in T2D patients. Therefore, variations in HLA genotypes might be used as genetic markers for prediction and potentially management of neuropathy in T2D patients.展开更多
Blast,a disease caused by Magnaporthe oryzae,is a major constraint for rice production worldwide.Introgression of durable blast resistance genes into high-yielding rice cultivars has been considered a priority to cont...Blast,a disease caused by Magnaporthe oryzae,is a major constraint for rice production worldwide.Introgression of durable blast resistance genes into high-yielding rice cultivars has been considered a priority to control the disease.The blast resistance Pik locus,located on chromosome 11,contains at least six important resistance genes,but these genes have not been widely employed in resistance breeding since existing markers hardly satisfy current breeding needs due to their limited scope of application.In this study,two PCR-based markers,Pikp-Del and Pi1-In,were developed to target the specific In Del(insertion/deletion)of the Pik-p and Pi-1 genes,respectively.The two markers precisely distinguished Pik-p,Pi-1,and the K-type alleles at the Pik locus,which is a necessary element for functional genes from rice varieties.Results also revealed that only several old varieties contain the two genes,of which nearly half carry the K-type alleles.Therefore,these identified varieties can serve as new gene sources for developing blast resistant rice.The two newly developed markers will be highly useful for the use of Pik-p,Pi-1 and other resistance genes at the Pik locus in markerassisted selection(MAS)breeding programs.展开更多
Strawberry(Fragaria spp.)is a member of the Rosoideae subfamily in the family Rosaceae.The self-incompatibility(SI)of some diploid species is a key agronomic trait that acts as a basic pollination barrier;however,the ...Strawberry(Fragaria spp.)is a member of the Rosoideae subfamily in the family Rosaceae.The self-incompatibility(SI)of some diploid species is a key agronomic trait that acts as a basic pollination barrier;however,the genetic mechanism underlying SI control in strawberry remains unclear.Two candidate S-RNases(S a-and S^-RNase)identi fi ed in the transcriptome of the styles of the self-incompatible Fragaria viridis 42 were con fi rmed to be SI determinants at the S locus following genotype identi fi cation and intraspeci fi c hybridization using sel fi ng progenies.Whole-genome collinearity and RNase T2 family analysis revealed that only an S locus exists in Fragaria;however,none of the compatible species contained S-RNase.Although the results of interspeci fi c hybridization experiments showed that F.viridis(SI)styles could accept pollen from F.mandshurica(self-compatible),the reciprocal cross was incompatible.S a and S b-RNase contain large introns,and their noncoding sequences(promotors and introns)can be transcribed into long noncoding RNAs(lncRNAs).Overall,the genus Fragaria exhibits S-RNase-based gametophytic SI,and S-RNase loss occurs at the S locus of compatible germplasms.In addition,a type of SI-independent unilateral incompatibility exists between compatible and incompatible Fragaria species.Furthermore,the large introns and neighboring lncRNAs in S-RNase in Fragaria could offer clues about S-RNase expression strategies.展开更多
The amount of molecular marker information has considerable impact on the results of studies of crop germplasm genetic relationships in crop. The number of alleles required to reveal genetic relationship in maize inbr...The amount of molecular marker information has considerable impact on the results of studies of crop germplasm genetic relationships in crop. The number of alleles required to reveal genetic relationship in maize inbred lines is a theoretical issue that needs to be addressed. In this study, 112 pairs of SSR （simple sequence repeat） primers and 97 maize inbred lines were selected to study the relationship between the number of inbred lines and the number of SSR primers and alleles required for a stable cluster. The results showed that the number of SSR primers is not tightly associated with the stability of the cluster analysis results, while an increase in the number of alleles can significantly improve the stability of cluster analysis results. The number of inbred lines （X） is significantly associated with the number of alleles required for stable cluster analysis （Y）, and the regression equation is Y- 600.8xe（-15.9/x）. This equation can be used to calculate the number of SSR alleles required for a genetic relationship study of maize inbred lines. These results provide a reference for determining of SSR alleles number in genetic relationship analysis of maize inbred line and other crop germplasm.展开更多
Eating and cooking qualities（ECQs） of rice are important attributes due to its major influence on consumer acceptability. To better understand the molecular mechanism of the variation in ECQs, we investigated and co...Eating and cooking qualities（ECQs） of rice are important attributes due to its major influence on consumer acceptability. To better understand the molecular mechanism of the variation in ECQs, we investigated and compared the expressions among different alleles of the Waxy（Wx） gene and its effect on ECQs in specialty rice cultivars. The results showed that the accumulation of amylose was positively and significantly correlated to the level of mature Wx m RNA and granule-bound starch synthase I（GBSS I） in developing rice grain at 12 days after flowering. The amount of GBSS I and its activity together are the main factors controlling amylose synthesis. Differences in ECQs among five Wx allele types were investigated in samples from 15 rice varieties. The apparent amylose content（AAC） and gel consistency（GC） were similar in each type of Wx allele. The AAC followed the order, Wx^a type〉Wx^in type〉Wx^b type〉Wx^mq type〉wx. Contrary to this, the GC showed an opposite trend compared to AAC. There was a wide variation in rapid visco analyzer（RVA） profile among five Wx allele types, while varieties sharing a specified Wx allele had basically the similar RVA profile, although there was a slight difference in some RVA parameters, peak, hot paste and cool paste viscosities.展开更多
Objective:To compare the genotype frequencies of HLA class-ⅡDRB1 alleles in Giardia(G.)lamblia-infected children.Methods:A total of 490 Egyptian children aged 2-16 years were subjected to microscopic stool examinatio...Objective:To compare the genotype frequencies of HLA class-ⅡDRB1 alleles in Giardia(G.)lamblia-infected children.Methods:A total of 490 Egyptian children aged 2-16 years were subjected to microscopic stool examination to detect G.lamblia infection,and to exclude other intestinal pathogens.On the basis of their microscopic findings,a group of 80 children were chosen as giardiasis cases,another 80 children were confirmed as Giardia free control group by immunochromatographic test,and the remaining children were excluded.Both giardiasis and control groups were then subjected to blood examination to identify their genetic type of HLA-DRB1 alleles.Results:HLA class-ⅡDRB1*03:01 and DRB1*13:01 alleles were significantly associated with G.lamblia infection(P<0.001 for each variable).On the other hand,HLA class-ⅡDRB1*04:02,DRB1*10:01,DRB1*14:01 and DRB1*15:01 alleles were significantly demonstrated in Giardia free children.However,other HLA-DRB1 alleles did not show any significant association with giardiasis.Conclusions:HLA class-ⅡDRB1*03,DRB1*13,DRB1*04,DRB1*10,DRB1*14 and DRB1*15 alleles may be involved in the establishment of host immune response to G.lamblia infection.展开更多
AIM： To establish the most common vacA alleles in Helicobacter pylori （ H pylon） strains isolated from Chilean patients and its relationship with gastritis and gastroduodenal ulcers, METHODS： Two hundred and forty...AIM： To establish the most common vacA alleles in Helicobacter pylori （ H pylon） strains isolated from Chilean patients and its relationship with gastritis and gastroduodenal ulcers, METHODS： Two hundred and forty five Hpyloriclinical isolates were obtained from 79 biopsies from Chilean infected patients suffedng from gastrointestinal diseases. An average of 2-3 strains per patient was isolated and the vac4 genotype was analyzed by PCR and 3% agarose electrophoresis. Some genotypes were checked by DNA sequencing. RESULTS： The most prevalent vacA genotype in Chilean patients was slb ml （76%）, followed by sla ml （21%）. In oontrast, the s2 m2 genotype was scarcely represented （3%）. The slb ml genotype was found most frequently linked to gastropathies （P〈0.05） rather than ulcers. Ulcers were found more commonly in male and older patients. Curiously, patents IMng in dties located North and far South of Santiago, thecapital and largest Chilean city, carried almost exclusively strains with the slb ml genotype. In contrast, patients from Santiago and cities located South of Santiago carded strains with either one or both sla ml and slb ml genotypes. Regarding the s2 m2 genotype, comparison with GenBank sequences revealed that Chilean s2 sequence was identical to those of Australian, American, and Colombian strains but quite different from those of Alaska and India. CONCLUSION： Differences in geographic distribution of the s and m vacA alleles in Chile and a relationship of slb ml genotype with gastritis were found. Sequence data in part support a hispanic origin for the vacA genotype. Asymmetric distribution of genotypes slb ml and s2 m2 recedes H Pyloristrain distribution in Spain and Portugal.展开更多
Fertility restoration of cytoplasmic male-sterility in pepper （Capsicum annuum L.） is useful for commercial production of hybrid seeds. However, the mechanism of fertility restoration has not been determined. We pre...Fertility restoration of cytoplasmic male-sterility in pepper （Capsicum annuum L.） is useful for commercial production of hybrid seeds. However, the mechanism of fertility restoration has not been determined. We previously constructed a cDNA library and identified some genes related to fertility restoration in pepper using suppression subtractive hybridization technology. In this study, the expression patterns of 20 genes were investigated using semi-quantitative RT-PCR. Three genes expressed only in restorer lines, but not in sterility lines. Four genes expressed only in anther, but not in other organs. Among these 7 genes, the clone TG31 was observed to specifically express in anther of restorer lines. The work described here provides a comprehensive overview on the expression pattern of the genes that are induced by restorer alleles in pepper. It will also contribute to the current understanding of molecular networks for the regulation of fertility restoration.展开更多
Objective. To establish a PCR- SSP method for discriminating as many HLA- A* 02 alleles, which could easily be introduced into a routine laboratory. Methods. In this study we typed HLA- A* 02 polymorphisms by a sequen...Objective. To establish a PCR- SSP method for discriminating as many HLA- A* 02 alleles, which could easily be introduced into a routine laboratory. Methods. In this study we typed HLA- A* 02 polymorphisms by a sequence- specific primer (SSP) method, which involved round 1 and round 2 PCR reactions to detect 17 HLA- A* 02 alleles (they are HLA- A* 0201- 0217 alleles) covering exon 2 and exon 3. Results. We have found that DNA sample concentration and purity were the most important variables in determining the quality of the results. For identifying correct band size, the size marker used was important. We noticed that different PCR machines performed differently. By this method, we detected 20 HLA- A* 02 positive genomic DNA samples and found 4 kinds of HLA- A* 02 alleles. They were HLA- A* 0201, 0203, 0206 and 0210. Conclusion. The HLA- A* 02 PCR- SSP method was proven to be a reliable and easily applicable typing method. Our results suggest that the SSP described here provides an optimal HLA- A* 02 typing technique that may be useful in selecting donor- recipient pairs in bone marrow transplantation between unrelated individuals.展开更多
A new, improved version of the catalog of 182 alleles at the six Gli loci of common wheat(T.aestivum L.) shown in electrophoregrams of 128 standard genotypes was used for analysis of1060 cultivars and lines bred in th...A new, improved version of the catalog of 182 alleles at the six Gli loci of common wheat(T.aestivum L.) shown in electrophoregrams of 128 standard genotypes was used for analysis of1060 cultivars and lines bred in the 20 th century. The most frequent alleles in the studied germplasm occurred with frequencies of 18%–40%, with 30 unique alleles, one in each cultivar. Extremely high genetic diversity was found(average H for the six main Gli loci was0.870 ± 0.046), nearly identical in winter(H = 0.831) and spring(H = 0.856) wheats but differing among 28 groups of cultivars released in 22 countries. Each country or region was characterized by its own specific set of the most frequent Gli alleles, and the 28 cultivar groups formed five main relationship clusters if polymorphism at the six Gli loci was considered. However, different levels of similarity between groups of cultivars were found if polymorphism of the A, B, or D genomes of common wheat was tested separately. In general, the 20 th century germplasm of common wheat was differentiated and structured by country or region and cultivar type(spring or winter). Each elemental genome(in particular, A and D) contributed to the structure of the polymorphism studied. We propose that the structure of the wheat germplasm was a result of natural selection under the ecoclimatic conditions of cultivation specific to each country or region. As many as 27.4% of cultivars studied violated the requirement of the DUS rules for uniformity, being represented by mixtures of two or more closely related genotypes. However, the composition of a cultivar as a set of related but different genotypes may contribute to its adaptivity, and thereby to the known high plasticity of common wheat.展开更多
基金funded by the National Key Research and Development Program of China(2016YFD0101802)the Key Research and Development Project of Shaanxi Province(2019ZDLNY04-05)+1 种基金the National Basic Research Program of China(2014CB138102)the National Natural Science Foundation of China(30971770 and 31671693)。
文摘The ability of wheat to adapt to a wide range of environmental conditions is determined mostly by allelic diversity among genes regulating vernalization requirement.Vrn-1 is a major regulator of this requirement.In this study,two novel alleles of Vrn-A1 were discovered in Chinese cultivars:vrn-A1n was identified in two landraces,Jiunong 2 and Ganchun 16,and Vrn-A1o was detected in Duanhongmangmai.Both novel alleles showed a linked duplication in the promoter region.The common copy of these two alleles was identical to the recessive allele vrn-A1.Compared with the recessive allele vrn-A1,the other copy of vrn-A1n contained a 54-bp deletion in the promoter region and the distinct copy of Vrn-A1o contained an11-bp deletion in the promoter region.In segregating populations in the greenhouse under nonvernalizing(20–25°C)and long-day(16 h light)conditions,plants with the novel vrn-A1n allele did not head earlier than those with the recessive vrn-A1 allele.However,plants that were either homozygous or heterozygous for the novel Vrn-A1o allele headed earlier than those with the recessive vrn-A1 allele.To identify the novel allele with the small-sized product and facilitate screening,a DNA marker for the novel dominant allele Vrn-A1o was designed.Analysis of the novel-allele distribution showed that two cultivars carrying the vrn-A1n allele were dispersed in the northwestern spring wheat zone,and 12 cultivars carrying the dominant Vrn-A1o allele were widely distributed in the northwestern spring wheat zone,Xinjiang winter and spring wheat zone,Yellow and Huai River valley winter wheat zone,and QinghaiTibetan Plateau spring and winter wheat zone.Our study identifies useful germplasm and a DNA marker for wheat breeding.
文摘Genetic diversity at Gli_1, Gli_2 and Glu_1 loci was investigated in 89 Sichuan wheat (Triticum aestivum L.) landraces by using acid polyacrylamide gel electrophoresis (APAGE) and SDS_PAGE. In these landraces, a total of 32 gliadin and 3 high_molecular_weight (HMW) glutenin patterns were observed. In total, 14, 15 and 5 alleles were identified at Gli_1, Gli_2 and Glu_1, respectively. At each locus, the alleles in higher frequency were Gli_A1a (89%), Gli_B1h (46%), Gli_D1a (65%), Gli_A2a (64%), Gli_B2j (45%), Gli_D2a (48%), Glu_A1c (99%), Glu_B1b (99%) and Glu_D1a (100%). The Nei's genetic variation index (H) of Sichuan wheat landraces was 0.370?6, varying from 0 to 0.708?7. The highest genetic diversity was found at Gli_B2 locus, while the lowest was found at Glu_D1. The genetic diversity at Gli loci was higher than that of Glu_1 loci among these landraces, but it was much lower than that of modern wheat cultivars. These results indicated a narrow genetic base of Sichuan wheat landraces. In this study, “Chengdu_guangtou” had the identical gliadin and HMW_glutenin patterns with “Chinese Spring”, further supporting the proposal that “Chinese Spring” is a strain of “Chengdu_guangtou”.
文摘Genetic diversity at Gli_1, Gli_2 and Glu_1 loci was investigated in 32 accessions of Chinese endemic wheat by using acid polyacrylamide gel electrophoresis (APAGE) and sodium dodecyl sulfate (SDS)_PAGE. There were 8 gliadin and 3 high_molecular_weight (HMW)_glutenin patterns in 14 Yunnan hulled wheat ( Triticum aestivum ssp. yunnanese King) accessions, 9 gliadin and 4 HMW_glutenin patterns in 9 Tibetan weedrace ( T. aestivum ssp. tibetanum Shao ) accessions, and 9 gliadin and 5 HMW_glutenin patterns in 9 Xinjiang rice wheat ( T. petropavlovskyi Udacz. et Migusch.) accessions. One accession (i.e. Daomai 2) carried new subunits 2.1+10.1 encoded by Glu_D1. Among the three Chinese endemic wheat groups, a total of 10, 14 and 11 alleles at Gli_1 locus; 11, 14 and 12 alleles at Gli_2 locus; and 5, 6 and 8 alleles at Glu_1 locus were identified, respectively. Among Yunnan hulled wheat, Tibetan weedrace and Xinjiang rice wheat, the Nei's genetic variation indexes were 0.3798, 0.5625 and 0.5693, respectively. These results suggested that Tibetan weedrace and Xinjiang rice wheat had higher genetic diversity than Yunnan hulled wheat.
基金Supported by Research Project from Education Department of Guangxi(200807MS065)Mathematical Modeling in Population Genetics from Talents Scheme of Universities in Guangxi~~
文摘This paper studies the offspring＇s genotype frequency of the selfing population on multiple alleles with limited loci.A recursive algorithm is given for it.It is discovered that the genotype frequency of homozygous gene of limited loci increases by generations.Relative increment reduces by generations and the genotype frequency tends to a definite value finally.The genotype frequency of limited loci with hybrid gene tends to 0 finally.But it is possibility that the genotype frequency increases in previous generations then reduces later.It is found that the number of the hybrid gene are more,the speeds tending to 0 are quicker.
基金This work was supported by "948" Project of China (No. 2001-361), Chinese National Programs for High Technology Research and Development (No. 2004AA222170), and Key Project of Chinese National Programs for Fundamental Research and Develop-ment (No. G2000016103).
文摘Genetic polymorphism of the major histocompatibility complex （MHC） B-LBⅡ gene was studied by amplification of exon 2 using PCR, followed by cloning and DNA sequencing in eight indigenous Chinese chicken populations. To reveal the genetic variation of the B-LB Ⅱ gene, 37 types of patterns detected by PCR-SSCP were investigated first, which would be used to screen novel B-LB Ⅱsequences within the breeds. The types of PCR-SSCP patterns and final sequencing allowed for the identification of 31 novel MHC B-LBⅡ alleles from 30 unrelated individuals of Chinese chickens that were sampled. These are the first designators for the alleles of chicken MHC B-LBⅡ gene based on the rule of assignment for novel mammalian alleles. Sequence alignment of the 31 B-LB Ⅱ alleles revealed a total of 68 variable sites in the fragment of exon 2, of which 51 parsimony informative and 17 singleton variable sites were observed. Among the polymorphic sites, the nucleotide substitutions in the first and second positions of the codons accounted for 36.76% and 35.29%, respectively. The sequence similarities between the alleles were estimated to be 90.6%-99.5%. The relative frequencies of synonymous and nonsynonymous nucleotide substitutions within the region were 2.92%±0.94% and 14.64%±2.67%, respectively. These results indicated that the genetic variation within exon 2 appeared to have largely arisen by gene recombination and balancing selection. Alignment of the deduced amino acid sequences of the β1 domain coded by exon 2 revealed 6 synonymous mutations and 27 nonsynonymous substitutions at the 33 disparate sites. In particular, the nonsynonymous substitutions at the putative peptide-binding sites are considered to be associated with immunological specificity of MHC B-LB Ⅱ molecule in Chinese native chickens. These results can provide a molecular biological basis for the study of disease resistance in chicken breeding.
文摘AIM. To investigate the influence of HLA-DRB1 alleles and HBV genotypes on inberferon-α therapy for chronic hepatitis B. METHODS： HLA-DRBI＊03, ＊07, ＊09,＊12, ＊15 alleles were determined using polymerase chain reaction/sequence specific primer （PCR/SSP） technique in 126 patients with chronic hepatitis B and 76 normal control subjects in Shandong Province, and HBV genotypes were determined by nested-PCR analysis using type-specific primers in 126 patients. RESULTS： The positivity of HLA-DRB1＊07 allele in chronic hepatitis B group was significantly higher than that in normal control group （X^2 = 6.33, P〈0.025, RR = 2.37）. Among the 126 patients, genotype B was found in 38 （30.2%）, genotype C in 69 （54.8%）, and mixed genotype （B＋C） in 19 （15.0%）, genotypes D-F were not found. Among the 46 DRB1＊07（＋） patients, 7 were responders and 39 were non-responders among them （X^2 = 6.71, P〈0.05）. The positivity of HLADRB1＊07 and prevalence of HBV genotype C were significantly higher in non-responders than in responders. CONCLUSION： High positivities of HLA-DRB1 ＊07 allele and HBV genotype C are closely associated with the lower response to interferon-α therapy for chronic hepatitis B.
基金This work was supported by the Special Funds for Major State Basic Research Program (973) of China (No.G1999054107) the National Key Technologies R & D Program of China during the 15th Five-years Plan Period (No. 2001BA705B02)
文摘Objective To determine the distribution of HLA-B alleles in the Chinese Yi ethnic group and its association with HIV infection. Methods One hundred and six unrelated healthy HIV negative and 73 HIV positive Chinese Yi ethnic individuals were typed by PCR-SSP. Results The frequency of alleles B*07, B*35, and B*46 were increased in HTV-1 -positive subjects, whereas the alleles B*55, B*44 and B*78 were absent in the HIV-infected persons studied. The B*46 allele was present in a significantly higher gene frequency among HIV-1-positive individuals (P=0.02, OR=3.32, 95% CI=1.13-9.78) compared with control subjects. Conclusion HLA-B*46 may be associated with its susceptibility to HIV-1 infections.
基金supported by the National Natural Science Foundation of China(31730081)the National Science Fund for Distinguished Young Scholars(31425022)+2 种基金the National Natural Science Foundation of China(31572152)the National Science Fund of Jiangsu Province(BK20151429)the Fundamental Research Funds for the Central Universities(KYRC201601).
文摘Chrysanthemums are sensitive to waterlogging stress,and the development of screening methods for tolerant germplasms or genes and the breeding of tolerant new varieties are of great importance in chrysanthemum breeding.To understand the genetic basis of waterlogging tolerance(WT)in chrysanthemums,we performed a genome-wide association study(GWAS)using 92,811 single nucleotide polymorphisms(SNPs)in a panel of 88 chrysanthemum accessions,including 64 spray cut and 24 disbud chrysanthemums.The results showed that the average MFVW(membership function value of waterlogging)of the disbud type(0.65)was significantly higher than that of the spray type(0.55)at P<0.05,and the MFVW of the Asian accessions(0.65)was significantly higher than that of the European accessions(0.48)at P<0.01.The GWAS performed using the general linear model(GLM)and mixed linear model(MLM)identified 137 and 14 SNP loci related to WT,respectively,and 11 associations were commonly predicted.By calculating the phenotypic effect values for 11 common SNP loci,six highly favorable SNP alleles that explained 12.85—21.85%of the phenotypic variations were identified.Furthermore,the dosage-pyramiding effects of the favorable alleles and the significant linear correlations between the numbers of highly favorable alleles and phenotypic values were identified(r2=0.45;P<0.01).A major SNP locus(Marker6619-75)was converted into a derived cleaved amplified polymorphic sequence(dCAPS)marker that cosegregated with WT with an average efficiency of 78.9%.Finally,four putative candidate genes in the WT were identified via quantitative real-time PCR(qRT-PCR).The results presented in this study provide insights for further research on WT mechanisms and the application of molecular marker-assisted selection(MAS)in chrysanthemum WT breeding programs.
基金Supported by Shandong Provincial Natural Science Foundation,China,No. ZR2009CQ031
文摘AIM:To evaluate the association of human leukocyte antigen(HLA)-DQB1 alleles with hepatocellular carcinoma(HCC) through meta-analysis of published data.METHODS:Case-control studies on HLA-DQB1 allele association with HCC published up to January 2010 were included in the analyses.The odds ratios(ORs) of HLADQB1 allele distributions in HCC patients were analyzed and compared with healthy controls.The meta-analysis software REVMAN 5.0 was applied for investigating heterogeneity among individual studies and for summarizing all the studies.A meta-analysis was performed using fixed-effect or random-effect methods,depending on the absence or presence of significant heterogeneity.Seven case-control studies containing 398 cases and 594 controls were included in the final analysis.RESULTS:Among the five family alleles,two(DQB1*02 and DQB1*03) were found to be significantly associated with the risk of HCC.The combined OR for the association of DQB1*02 and DQB1*03 allele with the risk for HCC was 1.78(95% CI:1.05-3.03,P = 0.03) and 0.65(95% CI:0.48-0.89,P = 0.007),respectively.Among the 13 specific alleles,two(DQB1*0502 and DQB1*0602) were significantly associated with risk of HCC.The combined OR for the association of DQB1*0502 and DQB1*0602 allele with the risk for HCC was 1.82(95% CI:1.14-2.92,P = 0.01) and 0.58(95% CI:0.36-0.95,P = 0.03),respectively.No significant association was established for other HLA-DQB1 family alleles and specific alleles.CONCLUSION:Our results support the hypothesis that specific HLA-DQB1 allele families and alleles might influence the susceptibility or resistance to HCC,although it needs further investigations.
基金supported by the Tunisian“Ministère de l’Enseignement Supérieur et de la Recherche Scientifique”and“Ministerio de Economía y Competitividad-European Regional Development Fund,European Union”(AGL2016-77267-R and PID2019-109566RB-I00)The authors would like to gratefully thank“Sodon collection”(Bou-Selem,Tunisia)and Tunisian farmers for kindly providing plant material.
文摘Self-incompatibility(SI)to self-compatibility(SC)transition is one of the most frequent and prevalent evolutionary shifts in flowering plants.Prunus L.(Rosaceae)is a genus of over 200 species most of which exhibit a Gametophytic SI system.Peach[Prunus persica(L.)Batsch;2n=16]is one of the few exceptions in the genus known to be a fully selfcompatible species.However,the evolutionary process of the complete and irreversible loss of SI in peach is not well understood and,in order to fill that gap,in this study 24 peach accessions were analyzed.Pollen tube growth was controlled in self-pollinated flowers to verify their self-compatible phenotypes.The linkage disequilibrium association between alleles at the S-locus and linked markers at the end of the sixth linkage group was not significant(P>0.05),except with the closest markers suggesting the absence of a signature of negative frequency dependent selection at the S-locus.Analysis of SFB1 and SFB2 protein sequences allowed identifying the absence of some variable and hypervariable domains and the presence of additionalα-helices at the C-termini.Molecular and evolutionary analysis of SFB nucleotide sequences showed a signature of purifying selection in SFB2,while the SFB1 seemed to evolve neutrally.Thus,our results show that the SFB2 allele diversified after P.persica and P.dulcis(almond)divergence,a period which is characterized by an important bottleneck,while SFB1 diversified at a transition time between the bottleneck and population expansion.
基金funded by Vice-chancellor for Research and Technology,Hamadan University of Medical Sciences of Iran,No.9208072467
文摘The potential impact of human leukocyte antigen （HLA） genotype variations on development of diabetic peripheral neuropathy （DPN） is not well determined. This study aimed to identify the association of HLA class II alleles with DPN in type 2 diabetes （T2D） patients. Totally 106 T2D patients, 49 with DPN and 57 without DPN, and 100 ethnic-matched healthy controls were analyzed. Both groups of the patients were matched based on sex, age, body mass index （BMI） and duration of T2D. Polyneuropathy was diagnosed using electrodiagnostic methods. HLA-DRB1 and DQB1 genotyping was performed in all subjects by the polymerase chain reaction with sequence-specific primers （PCR-SSP） method. T2D patients with DPN showed higher frequencies of HLA-DRB1＊10 and DRB1＊12 alleles compared to control group （P = 0.04）. HLA-DQB1＊02 allele and HLA-DRB1＊07-DQB1＊02 haplotype were associated with a decreased risk for developing DPN in T2D patients （P = 0.02 and P = 0.05 respectively）. Also, patients with severe neuropathy showed higher frequencies of DRB1＊07 （P = 0.003） and DQB1＊02 （P = 0.02） alleles than those with mild-to-moderate form of neuropathy. The distribution of DRB 1 and DQB 1 alleles and haplotypes were not statistically different between all patients and healthy controls. Our findings implicate a possible protective role of HLA-DQB1＊02 allele and HLA-DRB1＊07-DQB1＊02 haplotype against development of peripheral neuropathy in T2D patients. Therefore, variations in HLA genotypes might be used as genetic markers for prediction and potentially management of neuropathy in T2D patients.
基金the National Natural Science Foundation of China(31640006)the China Postdocotral Science Foundation(2019M662219)+1 种基金the Youngth Program of Fujian Academy of Agricultural Sciences(YC2019004)the Projection of Public Welfare of Fujian Province(2017R1019-10)。
文摘Blast,a disease caused by Magnaporthe oryzae,is a major constraint for rice production worldwide.Introgression of durable blast resistance genes into high-yielding rice cultivars has been considered a priority to control the disease.The blast resistance Pik locus,located on chromosome 11,contains at least six important resistance genes,but these genes have not been widely employed in resistance breeding since existing markers hardly satisfy current breeding needs due to their limited scope of application.In this study,two PCR-based markers,Pikp-Del and Pi1-In,were developed to target the specific In Del(insertion/deletion)of the Pik-p and Pi-1 genes,respectively.The two markers precisely distinguished Pik-p,Pi-1,and the K-type alleles at the Pik locus,which is a necessary element for functional genes from rice varieties.Results also revealed that only several old varieties contain the two genes,of which nearly half carry the K-type alleles.Therefore,these identified varieties can serve as new gene sources for developing blast resistant rice.The two newly developed markers will be highly useful for the use of Pik-p,Pi-1 and other resistance genes at the Pik locus in markerassisted selection(MAS)breeding programs.
基金This work was supported by the National Natural Science Foundation of Chi na(Gr ant no.32072540,31872056)the Fun dame ntal Research Fun ds for the Central Universities(Grant no.KYZZ2021002)a project funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD).
文摘Strawberry(Fragaria spp.)is a member of the Rosoideae subfamily in the family Rosaceae.The self-incompatibility(SI)of some diploid species is a key agronomic trait that acts as a basic pollination barrier;however,the genetic mechanism underlying SI control in strawberry remains unclear.Two candidate S-RNases(S a-and S^-RNase)identi fi ed in the transcriptome of the styles of the self-incompatible Fragaria viridis 42 were con fi rmed to be SI determinants at the S locus following genotype identi fi cation and intraspeci fi c hybridization using sel fi ng progenies.Whole-genome collinearity and RNase T2 family analysis revealed that only an S locus exists in Fragaria;however,none of the compatible species contained S-RNase.Although the results of interspeci fi c hybridization experiments showed that F.viridis(SI)styles could accept pollen from F.mandshurica(self-compatible),the reciprocal cross was incompatible.S a and S b-RNase contain large introns,and their noncoding sequences(promotors and introns)can be transcribed into long noncoding RNAs(lncRNAs).Overall,the genus Fragaria exhibits S-RNase-based gametophytic SI,and S-RNase loss occurs at the S locus of compatible germplasms.In addition,a type of SI-independent unilateral incompatibility exists between compatible and incompatible Fragaria species.Furthermore,the large introns and neighboring lncRNAs in S-RNase in Fragaria could offer clues about S-RNase expression strategies.
基金supported by the Natural Science Foundation of Shandong Province,China (Y2007D52)the Improved Variety Project of Shandong Province (2008 No.6)
文摘The amount of molecular marker information has considerable impact on the results of studies of crop germplasm genetic relationships in crop. The number of alleles required to reveal genetic relationship in maize inbred lines is a theoretical issue that needs to be addressed. In this study, 112 pairs of SSR （simple sequence repeat） primers and 97 maize inbred lines were selected to study the relationship between the number of inbred lines and the number of SSR primers and alleles required for a stable cluster. The results showed that the number of SSR primers is not tightly associated with the stability of the cluster analysis results, while an increase in the number of alleles can significantly improve the stability of cluster analysis results. The number of inbred lines （X） is significantly associated with the number of alleles required for stable cluster analysis （Y）, and the regression equation is Y- 600.8xe（-15.9/x）. This equation can be used to calculate the number of SSR alleles required for a genetic relationship study of maize inbred lines. These results provide a reference for determining of SSR alleles number in genetic relationship analysis of maize inbred line and other crop germplasm.
基金financially supported by the National HighTech R&D Program of China(2012AA101103)the Natural Science Foundation of Hunan Province,China(11JJ3032)the Major Project of China for Cultivation Technology of New Varieties of Genetically Modified Organisms,Ministry of Science and Technology,China(2014ZX08009-024B and 2014ZX08009003-004-009)
文摘Eating and cooking qualities（ECQs） of rice are important attributes due to its major influence on consumer acceptability. To better understand the molecular mechanism of the variation in ECQs, we investigated and compared the expressions among different alleles of the Waxy（Wx） gene and its effect on ECQs in specialty rice cultivars. The results showed that the accumulation of amylose was positively and significantly correlated to the level of mature Wx m RNA and granule-bound starch synthase I（GBSS I） in developing rice grain at 12 days after flowering. The amount of GBSS I and its activity together are the main factors controlling amylose synthesis. Differences in ECQs among five Wx allele types were investigated in samples from 15 rice varieties. The apparent amylose content（AAC） and gel consistency（GC） were similar in each type of Wx allele. The AAC followed the order, Wx^a type〉Wx^in type〉Wx^b type〉Wx^mq type〉wx. Contrary to this, the GC showed an opposite trend compared to AAC. There was a wide variation in rapid visco analyzer（RVA） profile among five Wx allele types, while varieties sharing a specified Wx allele had basically the similar RVA profile, although there was a slight difference in some RVA parameters, peak, hot paste and cool paste viscosities.
文摘Objective:To compare the genotype frequencies of HLA class-ⅡDRB1 alleles in Giardia(G.)lamblia-infected children.Methods:A total of 490 Egyptian children aged 2-16 years were subjected to microscopic stool examination to detect G.lamblia infection,and to exclude other intestinal pathogens.On the basis of their microscopic findings,a group of 80 children were chosen as giardiasis cases,another 80 children were confirmed as Giardia free control group by immunochromatographic test,and the remaining children were excluded.Both giardiasis and control groups were then subjected to blood examination to identify their genetic type of HLA-DRB1 alleles.Results:HLA class-ⅡDRB1*03:01 and DRB1*13:01 alleles were significantly associated with G.lamblia infection(P<0.001 for each variable).On the other hand,HLA class-ⅡDRB1*04:02,DRB1*10:01,DRB1*14:01 and DRB1*15:01 alleles were significantly demonstrated in Giardia free children.However,other HLA-DRB1 alleles did not show any significant association with giardiasis.Conclusions:HLA class-ⅡDRB1*03,DRB1*13,DRB1*04,DRB1*10,DRB1*14 and DRB1*15 alleles may be involved in the establishment of host immune response to G.lamblia infection.
基金Supported by FONDECYT, Comision Nacional Cientifica y Tecnologica, Chile No.1000730 No.1030894 and No. 1000734 from and NIH No.DK54495
文摘AIM： To establish the most common vacA alleles in Helicobacter pylori （ H pylon） strains isolated from Chilean patients and its relationship with gastritis and gastroduodenal ulcers, METHODS： Two hundred and forty five Hpyloriclinical isolates were obtained from 79 biopsies from Chilean infected patients suffedng from gastrointestinal diseases. An average of 2-3 strains per patient was isolated and the vac4 genotype was analyzed by PCR and 3% agarose electrophoresis. Some genotypes were checked by DNA sequencing. RESULTS： The most prevalent vacA genotype in Chilean patients was slb ml （76%）, followed by sla ml （21%）. In oontrast, the s2 m2 genotype was scarcely represented （3%）. The slb ml genotype was found most frequently linked to gastropathies （P〈0.05） rather than ulcers. Ulcers were found more commonly in male and older patients. Curiously, patents IMng in dties located North and far South of Santiago, thecapital and largest Chilean city, carried almost exclusively strains with the slb ml genotype. In contrast, patients from Santiago and cities located South of Santiago carded strains with either one or both sla ml and slb ml genotypes. Regarding the s2 m2 genotype, comparison with GenBank sequences revealed that Chilean s2 sequence was identical to those of Australian, American, and Colombian strains but quite different from those of Alaska and India. CONCLUSION： Differences in geographic distribution of the s and m vacA alleles in Chile and a relationship of slb ml genotype with gastritis were found. Sequence data in part support a hispanic origin for the vacA genotype. Asymmetric distribution of genotypes slb ml and s2 m2 recedes H Pyloristrain distribution in Spain and Portugal.
基金supported by the National Key Technologies R&D Program of China (2006BAD01A7 and 2008BADB1B04)the Chinese Universities Scientific Fund (2009-2-06)the National Natural Science Foundation of China (31071806)
文摘Fertility restoration of cytoplasmic male-sterility in pepper （Capsicum annuum L.） is useful for commercial production of hybrid seeds. However, the mechanism of fertility restoration has not been determined. We previously constructed a cDNA library and identified some genes related to fertility restoration in pepper using suppression subtractive hybridization technology. In this study, the expression patterns of 20 genes were investigated using semi-quantitative RT-PCR. Three genes expressed only in restorer lines, but not in sterility lines. Four genes expressed only in anther, but not in other organs. Among these 7 genes, the clone TG31 was observed to specifically express in anther of restorer lines. The work described here provides a comprehensive overview on the expression pattern of the genes that are induced by restorer alleles in pepper. It will also contribute to the current understanding of molecular networks for the regulation of fertility restoration.
文摘Objective. To establish a PCR- SSP method for discriminating as many HLA- A* 02 alleles, which could easily be introduced into a routine laboratory. Methods. In this study we typed HLA- A* 02 polymorphisms by a sequence- specific primer (SSP) method, which involved round 1 and round 2 PCR reactions to detect 17 HLA- A* 02 alleles (they are HLA- A* 0201- 0217 alleles) covering exon 2 and exon 3. Results. We have found that DNA sample concentration and purity were the most important variables in determining the quality of the results. For identifying correct band size, the size marker used was important. We noticed that different PCR machines performed differently. By this method, we detected 20 HLA- A* 02 positive genomic DNA samples and found 4 kinds of HLA- A* 02 alleles. They were HLA- A* 0201, 0203, 0206 and 0210. Conclusion. The HLA- A* 02 PCR- SSP method was proven to be a reliable and easily applicable typing method. Our results suggest that the SSP described here provides an optimal HLA- A* 02 typing technique that may be useful in selecting donor- recipient pairs in bone marrow transplantation between unrelated individuals.
文摘A new, improved version of the catalog of 182 alleles at the six Gli loci of common wheat(T.aestivum L.) shown in electrophoregrams of 128 standard genotypes was used for analysis of1060 cultivars and lines bred in the 20 th century. The most frequent alleles in the studied germplasm occurred with frequencies of 18%–40%, with 30 unique alleles, one in each cultivar. Extremely high genetic diversity was found(average H for the six main Gli loci was0.870 ± 0.046), nearly identical in winter(H = 0.831) and spring(H = 0.856) wheats but differing among 28 groups of cultivars released in 22 countries. Each country or region was characterized by its own specific set of the most frequent Gli alleles, and the 28 cultivar groups formed five main relationship clusters if polymorphism at the six Gli loci was considered. However, different levels of similarity between groups of cultivars were found if polymorphism of the A, B, or D genomes of common wheat was tested separately. In general, the 20 th century germplasm of common wheat was differentiated and structured by country or region and cultivar type(spring or winter). Each elemental genome(in particular, A and D) contributed to the structure of the polymorphism studied. We propose that the structure of the wheat germplasm was a result of natural selection under the ecoclimatic conditions of cultivation specific to each country or region. As many as 27.4% of cultivars studied violated the requirement of the DUS rules for uniformity, being represented by mixtures of two or more closely related genotypes. However, the composition of a cultivar as a set of related but different genotypes may contribute to its adaptivity, and thereby to the known high plasticity of common wheat.
