Haemoglobinopathies C and S in the Dogons.

The distribution of haemoglobins C and S was studied in a population of caste and non caste Dogons living in villages located on the plateau and scree regions in the Sangha department of Mali. Results showed a 15.77% prevalence of haemoglobinopathy AC. Haemoglobin C was found in both plateau and scree villages and equally among caste and non caste Dogons, while the homozygous form CC was absent in non Dogons. The prevalence of haemoglobinopathy AS was extremely low with a calculated frequency of 3.05%, allele S being restricted to areas where one is likely to encounter populations other than the Dogon people. Homozygotes SS were not detected and the phenotype SC was only rarely identified. An overall analysis of these data not only suggests that allele S is of recent introduction in the Dogons but also raises the question as to whether their origin is not the voltaic rather than the Manding plateau. Studies of marriage patterns and haplotypes currently in progress should enable resolution of this controversy.