THE sickle-cell trait has come to have more than a biological interest; its relevance has been extended by theories of racial migration developed to account for its distribution and frequency in various populations. December, 1953 issue of the American Anthropologist carried an article by Dr. Ronald Singer, The Sickle-Cell Trait in Africa, in which the etiology and distribution of the disease and trait were summarized. Singer posits the origin of the trait in the Mt. Ruwenzori region, and explains its distribution and ferquency in terms of dispersal from this point. This note is concerned with subsequent research and its relevance with respect to the conclusions presented by Singer. Prior to 1945, most investigators were convinced that the sickle-cell phenomenon was strictly a Negro trait and therefore a racial diagnostic. This view was supported by reports that the trait occurred only among African Negroes, or people who had undergone Negro admixture. However, it was then discovered that the sickle-cell trait was relatively common in parts of Italy (Silvestroni and Bianco 1946) and Greece (Choremis et al. 1951). There is little reason to assume that the high frequencies found in these areas are the result of Negro admixture. blood groups of the people in the Lake Copais region, who have the highest known frequency of the trait in Greece (17.7 percent), have a lower incidence of the typically Negro Ro chromosome than is found elsewhere in Greece (Choremis et al., ibid.). Morevoer, the trait has been found among the so-called Veddoid peoples (Todas, Badagas and Irulus) of the Nilgiri region in southern India, where a frequency of 30 percent is reported for one tribe (Lehmann and Cutbush 1952). situation was further complicated by the remarkably high frequency of the gene in widely separated areas in spite of the constant elimination of genes in cases dying of sickle-cell anemia. Theories of Negro migration were inadequate at best, since they could not account for such frequencies. Recent work by Allison (1954, 1955) has thrown new light on the whole problem and offers a convincing explanation of the frequency question. Allison's work strongly indicates that there is a relationship between the incidence and frequency of the trait and the presence and severity of subtertian malaria. Allison subjected 30 Luo men to malaria; 15 were trait carriers and 15 non-trait carrying controls. Fourteen of the 15 controls contracted malaria; only 2 of the 15 trait carriers got the disease, and both were milder than any case contracted by the trait-free control group. Although the sample was small, it is very unlikely that this result was due to chance. Allison's experiment indicates that heterozygosity for the sickle-cell gene affords protection against and/or lessens the effects of subtertian malaria. Subsequently, Allison has found further corroboration of his conclusions.