Hemoglobin variations on a small Bahamian island

ABSTRACT

Hemoglobin characteristics were investigated in 492 blood specimens collected in a small island community (1,450 inhabitants) in the Bahamas. Using two different methods, abnormal variants were detected in 20.3 percent of the sample, including genotypes AS, AC,AF(A/HPFH), SC and SF. Biodemographic evidence suggests that the origin and distribution of the hemoglobinopathies in this population have been influenced by historical migrations and genetic drift. The opportunity for drift has been particularly heightened by the "founder effect", the maintainance of small population size, a relatively endogamous mating structure, and restricted immigration. Health survey results reveal a wide discrepancy between the actual prevalence of abnormal hemoglobins and that indicated by informant reports.