Project description:Extensive genome analysis of pregnancy loss products by genome haplarithmisis. Pregnancy loss (PL) is the primary pregnancy complication, mostly caused by chromosomal abnormalities of the conceptus. However, the nature and prevalence of these abnormalities and the allocation of (ab)normal cells in embryonic and placental compartments during intrauterine development remains elusive. We analyzed 1,745 spontaneous PLs and found that ~50% were karyotypically normal. We applied genome haplarithmisis to 91 PL families with normal karyotypes, following whole-genome genotypes of the parents as well as of the extraembryonic mesoderm (EM) and chorionic villi (CV), representing embryonic and placental cells, of the product of conception (POC), which allowed characterizing genomic landscape of both lineages. 36.4% of these PLs have chromosomal aberrations not previously detected by karyotyping. In contrast to viable pregnancies where mosaic chromosomal abnormalities are often restricted to the CV, we find that in spontaneous abortions, the situation is reversed with a higher degree of mosaic chromosomal imbalances in EM rather than CV.
