Germline & Somatic Mosaicism: The 2014 Annual Scientific Meeting of the Human Genome Variation Society
Year: 2015
Type: article
Abstract: As genetic sequencing technologies continue to improve, researchers are progressively unraveling the cause and effect of germline variants on the human phenotype, disease, disease progression and efficacy of treatments.However, questions are now being asked as to the involvement of somatic variants on disease risk and how these variants can lead toward disease and aging.This includes determining their prevalence and distribution in what appears to be phenotypically normal tissues.The 2014 annual scientific meeting of the Human Genome Variation Society (HGVS; http://www.hgvs.org)was held on the 18th of October in San Diego, CA, to present research that is attempting to answer some of these questions.The theme of the meeting was "Germline & Somatic Mosaicism".In this meeting, we focused on technologies that enable analysis of germ line and somatic genetic differences, and on efforts to characterize their distribution, their association with human disease and clinical interpretation.The presentations illustrate the power of the marriage of wholesale genomics and retail genetics.Marc Greenblatt, of the University of Vermont, opened the meeting and chaired the first scientific session.The first presentation was by Laura Conlin from the Children's Hospital of Philadelphia, University of Pennsylvania, who spoke on "Somatic mosaicism and uniparental disomy" (UPD).UPD is present when all, or part of, a chromosome pair is from a single parent.UPD is detected by analyzing genomic DNA using a single-nucleotide polymorphism (SNP) array and observing a lack of heterozygosity in an extended haplotype of SNPs or a lack of alleles from one parent.UPD is particularly critical in areas that exhibit imprinting such as Prader-Willi syndrome, in which UPD can include all of chromosome 15, or Beckwith-Wiedemann syndrome, which usually involves segmental UPD in chromosome 11.UPD is not always associated with disease.In some cases, 100% UPD is a rescue of aneuploidy (e.g., postzygotic rescue of monosomy or trisomy).This can be observed in some cases of hidden trisomy where there is placental mosaicism but whole-blood DNA shows 100% UPD for the chromosome.UPD is identified as a mosaic in 17% of samples tested by diagnostic laboratories.As low as 5%-10% somatic mosaicism can be detected in a tissue sample.Some common UPD phenotypes include hearing
Source: Human Mutation
DOI: 10.1002/humu.22757
Language: English
Topic: Genomics and Rare Diseases
Subfield: Genetics
Domain: Life Sciences
Open Access status: bronze
OpenAlex ID: W1985603264