Targets of balancing selection in the human genome.

Mol Biol Evol 2009 Dec 27;26(12):2755-64. Epub 2009 Aug 27.

Department of Molecular Biology and Genetics, Cornell University, USA.

Balancing selection is potentially an important biological force for maintaining advantageous genetic diversity in populations, including variation that is responsible for long-term adaptation to the environment. By serving as a means to maintain genetic variation, it may be particularly relevant to maintaining phenotypic variation in natural populations. Nevertheless, its prevalence and specific targets in the human genome remain largely unknown. We have analyzed the patterns of diversity and divergence of 13,400 genes in two human populations using an unbiased single-nucleotide polymorphism data set, a genome-wide approach, and a method that incorporates demography in neutrality tests. We identified an unbiased catalog of genes with signatures of long-term balancing selection, which includes immunity genes as well as genes encoding keratins and membrane channels; the catalog also shows enrichment in functional categories involved in cellular structure. Patterns are mostly concordant in the two populations, with a small fraction of genes showing population-specific signatures of selection. Power considerations indicate that our findings represent a subset of all targets in the genome, suggesting that although balancing selection may not have an obvious impact on a large proportion of human genes, it is a key force affecting the evolution of a number of genes in humans.

Download full-text PDF

Source
http://dx.doi.org/10.1093/molbev/msp190DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2782326PMC
December 2009
31 Reads
96 Citations
9.110 Impact Factor

Publication Analysis

Top Keywords

balancing selection
16
human genome
8
genes
7
selection
5
method incorporates
4
incorporates demography
4
represent subset
4
approach method
4
subset targets
4
demography neutrality
4
genome-wide approach
4
tests identified
4
catalog genes
4
genes signatures
4
unbiased catalog
4
identified unbiased
4
neutrality tests
4
targets genome
4
findings represent
4
genome suggesting
4

Similar Publications