Identification of chromosomal abnormalities in miscarriages using single-nucleotide polymorphism arrays.

PURPOSE: Chromosome abnormalities are a known cause of miscarriage. A detailed chromosomal study in miscarriages is delineated using high-throughput technologies.

METHODS

564 miscarriages were collected, and the chromosomal abnormalities, including triploidy, trisomy, monosomy, uniparental disomy, and chromosomal deletions/duplications in miscarriages, were detected by high-throughput single-nucleotide polymorphism (SNP) array.

RESULTS

There were 336 (59.6%) miscarriages with chromosomal abnormalities, including 325 (57.6%) miscarriages with pathogenic variants and 11 (2%) miscarriages with variations of unknown significance (VOUS). The remaining 228 (40.4%) miscarriages had no clinically relevant chromosomal variants. Among the 325 miscarriages with pathogenic variants, 23 miscarriages had triploidy and two miscarriages showed genome-wide uniparental disomy. Trisomy was found in 225 miscarriages and involved nearly every chromosome. Monosomy X was found in 39 miscarriages. Also, 32 miscarriages were with partial chromosomal deletions/duplications, particularly in 8p23 and Xp22 regions.

CONCLUSIONS

Our results confirmed that trisomy and monosomy X are potentially the most common causes of miscarriage. We also showed that chromosomal pathogenic deletions/duplications are involved with miscarriage. However, still nearly 40% of miscarriages had no chromosomal variants detected by SNP array. This may be attributed to a single gene mutation that requires high-throughput sequencing.