Identification of Chromosomal Abnormalities in Early Pregnancy Loss Using a High-Throughput Ligation-Dependent Probe Amplification-Based Assay

Abstract

Embryonic chromosomal abnormalities are the major cause of miscarriage. An accurate, rapid, and cheap method of chromosome analysis in miscarriage is warranted in clinical practice. Thus, a high-throughput ligation-dependent probe amplification (HLPA)-based method of detecting aneuploidies and copy number variations in miscarriage was developed. A total of 1060 cases of miscarriage were assessed. Each specimen was subjected to quantitative fluorescence (QF)-PCR/HLPA and chromosomal microarray analysis (CMA) in parallel. All 1060 samples were successfully analyzed using both methods; of these samples, 1.7% (18/1060) were identified as having significant maternal cell contamination. Among the remaining 1042 cases without significant maternal cell contamination, QF-PCR/HLPA reached a diagnostic yield of 59.6% (621/1042), which is comparable to the yield of 60.3% (628/1042) with CMA. Compared with CMA results, the sensitivity and specificity of QF-PCR/HLPA in the identification of total pathogenic chromosomal abnormalities were 98.9% and 100%, respectively. Furthermore, the overall prevalence of chromosomal abnormalities in cases of spontaneous abortion was not significantly different from that in cases of recurrent miscarriage (61.3% versus 58.5%). In summary, QF-PCR/HLPA rapidly and accurately identified chromosomal abnormalities at a comparable performance and lower cost as compared with CMA. Combining simplicity and accuracy with cost-effectiveness, QF-PCR/HLPA may serve as a promising approach to routine genetic testing in miscarriage in clinical practice.