Abstract
Introductions: Complex chromosome rearrangement (CCR) is a structural rearrangement involving more than two breakpoints. CCR carriers are at high risk for phenotypic abnormalities or reproductive failure, such as chromosomal abnormalities in fetuses and infertility. In this study, we presented a carriers with chromosome (3,18) balanced translocation, whose fetus had duplications in chromosome 3 and deletions in chromosome 10 demonstrated by chromosomal microarray analysis (CMA).By revealing the cryptical translocation, we aimed to provide CCR carriers with more accurate risk assessment of abnormal pregnancy and better assisted reproduction with CMA and next generation sequencing(NGS).Results: By using the high resolution of GTG-banding technology, a cryptical translocation in chromosome 10 was found and the karyotype of the carrier was revised as 46,XY,t(3;10;18) (p26.3;q26.1;q21.1).In the cycle of preimplantation genetic diagnosis (PGD),21 oocytes were retrieved, and 15 were fertilized. At last 7 embryos were biospied and sent to diagnosis by next generation sequencing(NGS).Unfortunately, none of the NGS results from the 7 biopsy embryos were normal. Combining previous literature and our results, we assessed the odds of a balanced embryo in a CCR carrier to be about 9.3%(28/302).The transferable embryo rate was approximately 71.4%(20/28) and healthy live born delivery rate was 55%(11/20).Conclusions: NGS and CMA featured high automation, relatively low cost, high throughput, and high repeatability, which made them commonly used during prenatal diagnosis and PGD. The multiple technology combination can provide more accurate diagnosis and better fertility services for CCR patients.
A two‐year prospective study assessing the performance of fetal chromosomal microarray analysis and next‐generation sequencing in high‐risk pregnancies
