講演情報
[S9-3]New aspects of numerical and structural alterations in human chromosomes
○深見 真紀 (国立成育医療研究センター 分子内分泌研究部)
Recent advances in cytogenetic and molecular technologies, including array-based comparative genomic hybridization (CGH), SNP+CGH arrays, whole genome sequencing, and optical genome mapping, enabled researchers to characterize several numerical and structural alterations of chromosomes. Using these technologies. we have studied chromosomal alterations in patients with congenital disorders. First, we identified large de novo rearrangements on five paternally inherited chromosomes in a boy with congenital anomalies. Genomic analyses of the boy suggested that during spermatogenesis, a “transient multifocal genomic crisis” can introduce several chromothriptic and non-chromothriptic changes into the genome. Second, we found a patient with a small supernumerary marker chromosome. Based on the results of this case, we propose that chromothripsis-mediated incomplete trisomy rescue underlies various chromosomal changes including small supernumerary marker chromosomes and uniparental disomy. Lastly, we examined the pattern of X chromosome inactivation (XCI) in girls with imprinting disorders due to full uniparental disomy. The results suggested that aneuploid rescue precedes XCI and increases the incidence of XCI skewness by reducing the size of the embryonic progenitor cell pools. This symposium aims to discuss new aspects of chromosomal alterations.