Cooley's anaemia among the tanka of South China

Haemoglobin studies in 100 adult, unrelated Tanka patients and in 20 newborn Tanka infants are reported. In the former group 4 had β-thalassaemia, 3 had heterozygous α-thalassaemia and one had haemoglobin H disease. In the latter, one, a stillborn hydropic infant, had 73% haemoglobin Bart's in the cord blood. The history of the Tanka is briefly reviewed and it is concluded that they are the descendants of a pre-Han-Chinese autochthonous tribe who have lived in isolation. The finding of the gene of Cooley's anaemia among them lends support to the hypothesis previously advanced that the widespread distribution of the gene among the Mongoloids is best interpreted by assuming that the mutation occurred in a stock common to all, that is, in prehistoric times.