Somatic clones heterozygous for recessive disease alleles of BMPR1A exhibit unexpected phenotypes in Drosophila
- Stowers Institute for Medical Research, United States
Abstract
The majority of mutations studied in animal models are designated as recessive based on the absence of visible phenotypes in germline heterozygotes. Accordingly, genetic studies primarily rely on homozygous loss-of-function to determine gene requirements, and a conceptually-related 'two-hit model' remains the central paradigm in cancer genetics. Here we investigate pathogenesis due to somatic mutation in epithelial tissues, a process that predominantly generates heterozygous cell clones. To study somatic mutation in Drosophila, we generated inducible alleles that mimic human Juvenile polyposis-associated BMPR1A mutations. Unexpectedly, four of these mutations had no phenotype in heterozygous carriers but exhibited clear tissue-level effects when present in somatic clones of heterozygous cells. We conclude that these alleles are indeed recessive when present in the germline, but nevertheless deleterious when present in heterozygous clones. This unforeseen effect, deleterious heteromosaicism, suggests a 'one-hit' mechanism for disease initiation that may explain some instances of pathogenesis associated with spontaneous mutation.
Data availability
All primary data is available at the Stowers Institute Original Data Repository (https://www.stowers.org/research/publications/libpb-1261)
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LIBPB-1261Available at the Stowers Institute Original Data Repository.
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Author details
Funding
Stowers Institute for Medical Research
- Matthew C Gibson
National Institutes of Health (GM111733)
- Matthew C Gibson
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2018, Akiyama et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Somatic clones heterozygous for recessive disease alleles of BMPR1A exhibit unexpected phenotypes in Drosophila
eLife 7:e35258.
https://doi.org/10.7554/eLife.35258
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