摘要
目的探讨DNA片段差异性分级分离法对孕妇血浆中胎儿游离DNA富集的效果。方法取孕中期孕妇静脉血5ml,分别提取血浆中游离DNA和白细胞DNA,用琼脂糖凝胶电泳分离DNA片段,回收<400、400～1000、1000～3000bp部分凝胶中的DNA,扩增16个短串联重复序列(STR)遗传标志位点,同时扩增和检测孕妇白细胞基因组DNA和胎儿羊水细胞基因组DNA作对照,然后,用ABI310基因分析仪检测。结果共检测3例孕妇外周血标本48个STR位点,其中有意义位点(即胎儿父源性等位基因可与孕妇等位基因区分的STR位点)31个。从血浆总DNA、<400、400～1000和1000～3000bpDNA组中成功检测到胎儿等位基因的位点数占有意义位点数的百分比分别为6.45%、29.03%、38.71%和9.68%,各组检出成功率的差异有统计学意义(χ2=13.432,P=0.004),而<400和400～1000bpDNA组成功率较高。结论孕妇血浆DNA中短片段组分(<1000bp)胎儿DNA含量相对较高,有望应用于无创性胎儿产前诊断。
Objective To discuss the enrichment method of fetal DNA from maternal plasma onsize-fractionated separation. Methods Antecubital venous blood （ 5 ml from each pregnant woman ） wascollected in EDTA-containing tubes. DNA was extracted from plasma and white blood cells, separately. The DNA was fractionated by agarose gel electrophoresis. Three sections of 〈 400, 400 -1 000 and 1 000 -3000 bp were collected and extracted. Short tandem repeat （STR） markers were detected by capillaryelectrophoresis on an ABI 310 gene analyzer. To amplify and detect the STRs genotypes of maternal genomicDNA and fetal genomic DNA as comparison. Results Forty-eight loci of three samples were detected and theamount of the loci that could be used to discriminate the fetal allele from paternal inheritance was thirty-one.The ratio of fetal DNA detection in total circulatory DNA, the section of 〈 400 bp, the section of 400 -1000bp DNA and the section of 1 000 -3 000 bp DNA were 6. 45% ,29. 03% ,38. 71% and 9. 68%respectively. The difference was significant （x^2 = 13. 432, P = 0. 004）. The section of 〈 400 bp DNA andthe section of 400 -1 000 bp DNA were both more successful. Conclusion The short fragment （ the sectionof 〈 1 000 bp DNA） of maternal plasma had more fetal DNA content and could be hopeful in non-invasiveprenatal diagnosis.
出处
《中华检验医学杂志》
CAS
CSCD
北大核心
2006年第3期233-235,共3页
Chinese Journal of Laboratory Medicine
