On Oct. 29, 2007, the International HapMap Consortium announced it had published an analyses of its second-generation map of human genetic variation, which contains more than 3.1 million genetic variants. The improved HapMap helps researchers find DNA variants that influence the risk of disease and other traits.

Any 2 humans are more than 99% identical at the genetic level. The small fraction of DNA that varies among people can help explain differences in susceptibility to disease, response to drugs or reaction to environmental factors. The initial version of the HapMap was published in 2005 by the International HapMap Consortium, a public-private partnership of researchers and funding agencies from around the world.