Application of copy number variation analysis based on next-generation sequencing in the genetic analysis of missed abortion chorionic villi / 中华妇产科杂志

ABSTRACT

Objective To investigate the value of copy number variation analysis based on next-generation sequencing (NGS-CNVA) in the genetic analysis of missed abortion chorionic villi. Methods From August 2012 to May 2014, chorionic villi from 74 cases of missed abortion at 6-13 gestational weeks in Haidian Maternal and Child Health Hospital were collected and analyzed by karyotype analysis and NGS-CNVA. The results of the two methods were compared. Results (1) Karyotype analysis was carried out for the villi from the 74 missed abortion patients. Thirty cases were euploid, 26 cases were aneuploid, while 18 cases had structural abnormalities. The resolution of the karyotyping was 320 bands and the average report time was 22 days. (2) All of the 74 samples obtained NGS-CNVA results and the report time was 7-10 days. (3) The NGS-CNVA results of 56 cases were consistent with karyotype. Among them, 28 cases (28/56, 50%) had no copy number variants (CNV), and 19 cases (19/56, 34%)had CNV between 1 Mb and 10 Mb. 9 cases (9/56,16%) had CNV≥10 Mb found by NGS-CNVA, but not found by karyotyping. (4) According to the results of NGS-CNVA, karyotype were reviewed. The reviewed results found 7 cases with CNV<10 Mb and 3 cases with CNV≥10 Mb in 30 cases which got normal karyotype results at the first analysis. (5) Among the 18 cases of structural abnormalities, 6 cases were Robertsonian translocation. Sequencing technology could confirm the specific area of chromosome deletion/duplication in 8 cases, but could not locate them. Conclusions NGS-CNVA has lower failure rate, higher resolution, lower specimen requirement and shorter report time than karyotype analysis when used for the genetic analysis of missed chorionic villi . NGS-CNVA could be a useful genetic analysis method for the missed abortion villi.