A variant in a gene called HMGA2 is associated with differences in adult and childhood height in the general population, reports a study to be published online in Nature Genetics. This is the first such common variant to be reproducibly associated with human stature, and likely heralds a new wave of studies associating genetic variation with non-disease-related complex traits in humans.
Studies of twins have shown that up to 90% of the normal variation in human height is due to genetic variation, with such variants likely to be distributed among a large number of genes. A large consortium of investigators led by Timothy Frayling, Joel Hirschhorn, and Mark McCarthy carried out a genome-wide association study of nearly 5,000 individuals, and found two variants very close to HMGA2 to be associated with variation in height. A follow-up study of more then 19,000 individuals confirmed the association.
HMGA2 is an excellent candidate to be associated with height, as rare, severe mutations in the gene cause dramatic alterations of body size in mice and humans. Although the effect of these common HMGA2 variants is small-- explaining approximately 0.3% of population variation in height, or approximately 0.4 cm increased height per copy in an individual-- the success of the study suggests that additional genes will soon be associated with height and other visible traits in humans.
Timothy Frayling (Peninsula Medical School, Exeter, UK)
Abstract available online.
(C) Nature Genetics press release.
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