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Structural diversity and African origin of the 17q21.31 inversion polymorphism

NCJ Number
Nature Genetics Volume: 44 Dated: 2012 Pages: 872-880
Date Published
9 pages

In this paper, the authors examine the origins of genetic diversity of the 17q21.31 inversion polymorphism in a group of individuals, specifically focusing on African populations, and identify a likely ancestral inverted haplotype which lacks certain duplications found in European populations.


The 17q21.31 inversion polymorphism exists either as direct (H1) or inverted (H2) haplotypes with differential predispositions to disease and selection. The authors investigated its genetic diversity in 2,700 individuals, with an emphasis on African populations. They characterize eight structural haplotypes due to complex rearrangements that vary in size from 1.08–1.49 Mb and provide evidence for a 30-kb H1-H2 double recombination event. The authors show that recurrent partial duplications of the KANSL1 gene have occurred on both the H1 and H2 haplotypes and have risen to high frequency in European populations. The authors identify a likely ancestral H2 haplotype (H2′) lacking these duplications that is enriched among African hunter-gatherer groups yet essentially absent from West African populations. Whereas H1 and H2 segmental duplications arose independently and before human migration out of Africa, they have reached high frequencies recently among Europeans, either because of extraordinary genetic drift or selective sweeps. (Publisher Abstract Provided)

Date Published: January 1, 2012