Project description:The project aim is to evaluate the role of whole-genome aCGH for prenatal diagnosis in Hong Kong. Array CGH was performed on 220 samples recruited prospectively as the first-tier test study; and on 150 samples with abnormal ultrasound findings and normal karyotypes as a further-test study using NimbleGen CGX-135K oligonucleotide arrays. After the exclusion of common aneuploidies in the first-tier study, clinically significant CNVs are detected in 23/220 samples. In the further test study, clinically significant CNVs are detected in 9/150 samples, which showed CGX array has an increased diagnostic yield of about 6% compared with conventional cytogenetic methods. CNVs of unclear clinical significance are detected in only 10/370 (2.7%) samples. Only data from sample with positive findings are included in this experiment submission (the samples with normal results are not included here).
