In “Are humans riddled with rare genetic variants?: Blossoming of variation followed explosion in population size” (Nature, 17 May 2012), Erika Check Hayden reports,
By sequencing more people more thoroughly than ever before, researchers have affirmed that rare genetic variants — those carried by fewer than five people in a thousand — are widespread and likely to have an important role in human health.
Two studies1, 2 published today in Science find that most human genetic variants are rare, and that rare variants are more likely than common ones to affect the structure or function of proteins, and therefore to have biological or medical consequences. The papers, along with another study3 published last week in Science, all conclude that humans carry such a high load of rare variants because the species experienced a population growth spurt that began a few millenia after the adoption of agriculture, which occurred about 10,000 years ago.
The three studies add to a growing body of knowledge that has profound implications for researchers investigating the genetic roots of disease.
Or, for that matter, the genetic roots of health?
Take home point: “The findings suggest that researchers will need to revamp their current methods for deciphering gene function, … ”