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

To explore the genetic cause for abnormal pregnancies through detecting chromosomal copy number variations (CNVs) in abortic tissues by next generation sequencing (NGS).

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).

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.

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.