Medical Genetics Laboratories, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA.
Prenat Diagn. 2012 Apr;32(4):351-61. doi: 10.1002/pd.3861.
To evaluate the results of prenatal chromosomal microarray analysis (CMA) on >1000 fetal samples referred for testing at our institution and to compare these data to published reports.
High resolution CMA was offered to women undergoing amniocentesis or chorionic villus sampling. Parental samples were obtained concurrently to exclude maternal cell contamination and assist interpretation of copy number variations.
Clinically significant copy number variations were observed in 85/1115 cases (7.6%) overall, and in 45/1075 cases (4.2 %) if 40 abnormal cases with known chromosome abnormalities or familial genomic imbalances were excluded. Eighteen of the 1115 cases had variants of unclear clinical significance (1.6%). Indications yielding the most clinically significant findings were abnormal karyotype/fluorescence in situ hybridization (26/61, 42.6%), family history of chromosomal abnormality (13/137, 9.5%), abnormal ultrasound (38/410, 9.3%), abnormal serum screening (2/37, 5.4%) and advanced maternal age (5/394, 1.3%). Of 1075 cases having no previously known cytogenetic abnormality or family history, 18 (1.7%) had clinically significant genomic changes undetectable by conventional prenatal chromosome analysis.
Current experience confirms that the detection rate of CMA for prenatal chromosomal abnormalities surpasses that of conventional karyotype analysis and continues to improve with higher resolution arrays, while maintaining a low frequency of results of unclear clinical significance.
评估在本机构进行检测的>1000 例胎儿样本的产前染色体微阵列分析（CMA）结果，并将这些数据与已发表的报告进行比较。
对接受羊膜穿刺术或绒毛膜取样的女性提供高分辨率 CMA。同时获取父母样本，以排除母体细胞污染并协助解释拷贝数变异。
总体而言，在 1115 例中有 85 例（7.6%）观察到临床意义显著的拷贝数变异，若排除 40 例已知染色体异常或家族性基因组失衡的异常病例，则有 45 例（4.2%）。1115 例中有 18 例（1.6%）存在临床意义不明确的变异。产生最显著临床发现的指征包括异常核型/荧光原位杂交（26/61，42.6%）、染色体异常家族史（13/137，9.5%）、异常超声（38/410，9.3%）、异常血清筛查（2/37，5.4%）和高龄产妇（5/394，1.3%）。在 1075 例无先前已知细胞遗传学异常或家族史的病例中，18 例（1.7%）有常规产前染色体分析无法检测到的临床意义显著的基因组变化。
目前的经验证实，CMA 检测产前染色体异常的检出率超过传统核型分析，并随着更高分辨率的阵列不断提高，同时保持不明确临床意义结果的低频率。
