The International HapMap Project was a consortium of researchers in Canada, China, Japan, Nigeria, the United Kingdom, and the United States, organized to produce a human haplotype map by genotyping 270 samples from four populations with geographically diverse ancestry (1, 2). These samples in-cluded 30 mother–father–adult child trios from the Yoruba in Ibadan, Nigeria; 30 trios from the CEPH (Centre d’Etude du Polymorphisme Humain) collection of Utah residents of Northern and Western European ancestry; 45 unrelated Han Chinese individuals in Beijing, China; and 45 unrelated Japanese individuals in Tokyo, Japan. Approximately 1 million SNPs were genotyped and their LD patterns characterized in Phase I of the project. A description was published in 2005 (1), but the data were available long before this and were central to several early genomic discoveries in complex diseases (5, 6). The Phase II HapMap of more than 3 million SNPs was published in 2007 (7).
