Freezer anthropology: new uses for old blood

Archived blood fractions (plasma, settled red cells, white cells) have prov ed to be a rich and valuable source of DNA for human genetic studies. Large numbers of such samples were collected between 1960 and the present for pr otein and blood group studies, many of which are languishing in freezers or have already been discarded. More are discarded each year because the usef ulness of these samples is not widely understood. Data from DNA derived fro m 10-35-year-old blood samples have been used to address the peopling of th e New World and of the Pacific. Mitochondrial DNA haplotypes from studies u sing this source DNA support a single wave of migration into the New World (or a single source population for the New World), and that Mongolia was th e likely source of the founding population. Data from Melanesia have shown that Polynesians are recent immigrants into the Pacific and did not arise f rom Melanesia.