[Identification of cryptic structural chromosomal aberrations in parents through detection of copy number variations in miscarriage tissues].

ABSTRACT

OBJECTIVE: To explore the genetic cause for abnormal pregnancies through detecting chromosomal copy number variations (CNVs) in abortic tissues by next generation sequencing (NGS). METHODS: NGS technique was used to detect CNVs in abortion tissues. Parental chromosomal karyotypes were predicted based on the results. The aberrant chromosomal segments of the parents were accurately mapped by G-banding karyotyping analysis and fluorescence in situ hybridization (FISH). RESULTS: In addition to numerical chromosomal aberrations, 12 microdeletion/microduplications were detected by NGS. For 8 families where both parents accepted chromosomal karyotyping, 4 carriers of chromosomal abnormalities were identified. One marker chromosome was missed by karyotyping analysis, and a mother was confirmed to carry a cryptic balanced translocation by FISH. CONCLUSION: NGS can facilitate detection of cryptic chromosomal translocations in couples with repeated pregnancy failure and is of great value for detecting abnormal CNVs for its high sensitivity.