Chromosome instability is common in human cleavage-stage embryos

Chromosome instability is a hallmark of tumorigenesis. This study establishes that chromosome instability is also common during early human embryogenesis. A new array-based method allowed screening of genome-wide copy number and loss of heterozygosity in single cells. This revealed not only mosaicism for whole-chromosome aneuploidies and uniparental disomies in most cleavage-stage embryos but also frequent segmental deletions, duplications and...