A sexual ornament in chickens is affected by pleiotropic alleles at HAO1 and BMP2, selected during domestication.

Johnsson M, Gustafson I, Rubin C, Sahlqvist A, Jonsson KB, Kerje S, Ekwall O, Kämpe O, Andersson L, Jensen P, Wright D

PLoS Genet. 8 (8) e1002914 [2012-08-30; online 2012-08-30]

Domestication is one of the strongest forms of short-term, directional selection. Although selection is typically only exerted on one or a few target traits, domestication can lead to numerous changes in many seemingly unrelated phenotypes. It is unknown whether such correlated responses are due to pleiotropy or linkage between separate genetic architectures. Using three separate intercrosses between wild and domestic chickens, a locus affecting comb mass (a sexual ornament in the chicken) and several fitness traits (primarily medullary bone allocation and fecundity) was identified. This locus contains two tightly-linked genes, BMP2 and HAO1, which together produce the range of pleiotropic effects seen. This study demonstrates the importance of pleiotropy (or extremely close linkage) in domestication. The nature of this pleiotropy also provides insights into how this sexual ornament could be maintained in wild populations.

NGI Uppsala (SNP&SEQ Technology Platform)

NGI Uppsala (Uppsala Genome Center)

National Genomics Infrastructure

PubMed 22956912

DOI 10.1371/journal.pgen.1002914

Crossref 10.1371/journal.pgen.1002914

pii: PGENETICS-D-11-02811
pmc: PMC3431302