Presentation Information

[OE2-3]Direct detection of loss of heterozygosity using the genome sequencing data of three-generation human families

Hyoenjeong Kim, Mikita Suyama (Division of Bioinformatics, Medical Institute of Bioregulation, Kyushu University, Fukuoka, Japan)
Loss of heterozygosity (LOH) is a genetic alteration that results from the loss of one allele at a heterozygous locus. This phenomenon can serve as a crucial source of genome diversity and is associated with diseases such as cancer. Although LOH is a functionally important genetic event, little is known about its nature; for example, its frequency and genomic distribution remain unclear. To perform this type of analysis with precision, data from single individuals and their parents are required. Whole-genome sequencing data of CEPH/Utah families motivated us to identify LOH. This dataset comprises large three-generation family units consisting of grandparents, parents, and several offspring in Utah in the United States.We identified LOH events over the whole-genome using 285 individuals from 33 families in Utah in the United States. We then assessed the characteristics of the LOH, which is an exclusively postzygotic event, by examining the correlation between the incidence of the event and the parents’ features, such as age and sex. Moreover, LOH events were classified into two groups, those existing in the germline and somatic cells, by investigating the mode of inheritance of the LOH. We thus confirmed that LOH is transmitted to progeny, showing that LOH is also present in the germline cells. Finally, we discovered that the occurrence of LOH is significantly associated with the inter-homolog distances, which reflect the chromosome territory.