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Following the Dynamics of Structural Variants in Experimentally Evolved Populations
Published on: February 3, 2023
Adaptive evolution of UGT2B17 copy-number variation
Yali Xue1, Donglin Sun, Allan Daly
1The Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton CB10 1SA, UK.
American Journal of Human Genetics
|September 2, 2008
Summary
The human UGT2B17 gene exhibits significant copy number variation and geographical differences. Researchers uncovered a 117 kb deletion, revealing insights into its evolutionary history and population-specific selection.
Area of Science:
- Genetics
- Evolutionary Biology
- Human Population Genetics
Background:
- The human UGT2B17 gene displays considerable copy number variation (CNV) across individuals and populations.
- Geographical differences in UGT2B17 CNV suggest a complex evolutionary history.
- Previous genomic reference sequences for this region were found to be misassembled.
Purpose of the Study:
- To investigate the evolutionary history and population genetics of the UGT2B17 gene.
- To correct the reference genome assembly for the UGT2B17 locus.
- To identify the molecular mechanisms underlying UGT2B17 CNV and its geographical distribution.
Main Methods:
- Corrected genome assembly to accurately represent UGT2B17 alleles.
- Identification of a 117 kb deletion polymorphism and its breakpoints.
- DNA resequencing of the UGT2B17 breakpoint region in diverse human populations and chimpanzees.
Main Results:
- The UGT2B17 polymorphism is a 117 kb deletion resulting from nonallelic homologous recombination.
- Unusually high genetic diversity was observed, with an estimated time to the most recent common ancestor of ~2.4-3.0 million years.
- Evidence suggests balancing selection in Europe and positive selection for the deletion in East Asia.
Conclusions:
- The UGT2B17 gene's CNV is shaped by complex evolutionary processes, including recombination and selection.
- Distinct evolutionary pressures in different continents have led to the observed population-specific patterns of UGT2B17.
- Understanding UGT2B17 variation is crucial for interpreting its role in human health and disease.
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