Bobs技术在胎儿染色体异常产前诊断中的应用

Application of BACs-on-Beads technology for prenatal diagnosis of fetal chromosomal abnormalities

目的:探讨将细菌人工染色体微球(Bobs)检测技术应用于胎儿染色体异常产前诊断的可行性。方法:选取7864例单胎中期妊娠孕妇(指征包括高龄、唐氏血清学筛查高风险、胎儿无创DNA检测高风险、不良生育史、胎儿超声结构或软指标异常、染色体病家族史等),用Bobs技术快速检测13、18、21、X、Y染色体的数目异常及9种微缺失综合征,并与常规羊水细胞染色体的G显带分析结果及基因芯片检测结果进行比较。结果:共检出302例各类异常,包括256例染色体非整倍体数目异常(含3例嵌合体及2例47,XXY合并Yq11.223、Yq11.23微重复),46例微缺失及微重复异常(含1例等臂X染色体),染色体非整倍体数目异常检测结果同G显带核型分析结果一致,有39例微缺失、微重复进行基因芯片检测,结果与Bobs一致。Bobs在检测数目异常+嵌合体及结构异常的灵敏度、特异性和准确性均为100.0%。结论:Bobs技术检测胎儿染色体非整倍体异常和9种微缺失综合征,是具有快速、可靠等特点的产前诊断方法。

Objective： To explore the feasibility of bacterial artmcial chromosome on beads （Bobs） detection technique for prenatal diagnosing fetal chromosomal abnormality. Methods：7864 pregnant women with single fetal were selected, which included women with aged over 35 years, high risk of Down＇s serology screening, abnormal result by fetal noninvasive prenatal test （NIPT）,abnormal childbearing history abnormal fetus by ultrasonography, family history of chromosomal diseases, and so on. The number of 13, 18, 21, X, Y chromosomes and 9 kinds of microdeletion syndrome were detected by Bobs technique. The results were compared with the results of G banding analysis and gene chip detection. Results：302 cases with abnormality were found in this study, including 256 abnormal chromosome aneuploidy （including 3 cases of chimeras and 2 cases 47, XXY with Yq11.223 and Yq11.23 microrepetition）, 46 cases of microdeletion and microduplication （including 1 cases of X isochromosome）. The results of abnormal chromosome aneuploidy cases were the same as those of G banding karyotype analysis. There were 39 cases of microdeletion and micro duplication. The results of gene chip detection were the same as that of Bobs. The sensitivity, specificity and accuracy of Bobs in detected abnormal chromosome aneuploidy and micro-deletion and mieroduplication were all 100.0%. Conclusion：Bobs technology is a fast and reliable prenatal diagnosis method for detecting fetal chromosomal aneuploidy ab normalities and 9 kinds of microdeletion syndrome.