微阵列比较基因组杂交技术在产前诊断胎儿颅内间隙异常的应用

Application research on prenatal diagnosis of the fetuses with intracranial abnormal clearance by array-based comparative genomic hybridization

目的:探讨颅内间隙异常胎儿的基因组拷贝数变化。方法:对颅内间隙异常而常规染色体核型分析未见异常的胎儿采用微阵列比较基因组杂交技术(array-based comparative genomic hybridization,array-CGH)进行基因组拷贝数变化的检测分析(copy number variations,CNVs)。结果:44例头部间隙发育异常但常规G显带染色体核型分析正常的胎儿,检出致病性染色体微缺失3例,微重复3例,异常检出率13.6%(6/44),其中透明隔腔消失或缩小、侧脑室前角扩张和或伴侧脑室体部增宽的14例,发现微缺失3例、微重复2例,异常检出率35.7%;单纯侧脑室体部增宽30例,包括27例轻度增宽和3例重度增宽,在重度增宽病例中发现1例存在染色体微重复,异常检出率3.3%(1/30)。结论:胎儿透明隔腔发育异常、侧脑室前角增宽时胎儿亚显微结构异常的发生率高,array-CGH可为临床遗传诊断提供依据。

Objective： To investigate the genomic copy number variations （CNVs） in the fetuses with intracranial abnormal clear- ance. Methods： Genomic copy number variations of the fetal intracranial abnormal clearance with nomal chromosomal karyotype was scanned and analyzed by array - CGH. Results. 3 cases of microdeletion and 3 cases of microduplication were detected with the abnormal detection rate of 13.64% （6/44） . 3 cases of microdeletion and 2 cases of microduplication were detected in the 14 casese with absence of cavum septum pellucidum and the anterior horn of lateral ventricle dilatation （35.71%）, among the 30 fetuses of ventriculomegaly, there were 27 with mild ventriculomegaly, 3 with severe ventriculomegaly, only 1 case of microduplication in severe ventriculomegaly, the abnormal detec- tion ratec was 3.3% （1/30） . Conclusion： Fetal cavum septum pellucidum abnormal and the anterior horn of lateral ventricle dilatation have high incidence of microdeletion and microduplication, array - CGH can provide the basis for clinical ~enetic diaznosis.