Population genetic studies of the Aka Pygmies (Central Africa)

Summary Blood samples collected in a single Pygmy tribe, the Aka, living in Bokoka district (Central African Empire) were investigated with respect to the phenotype and gene frequencies of the following 12 enzyme systems: acid phosphatase, adenosine deaminase, adenylate kinase, carbonic anhydrase, esterase D, glucose-6-phosphate dehydrogenase, malate dehydrogenase, phosphoglucomutase 1, phosphoglucomutase 2, phosphogluconate dehydrogenase, superoxide dismutase and serum cholinesterase variants (locus E₁ and E₂). The data obtained in the study of genetic polymorphisms of this isolated and inbred population show a specific pattern with the following characteristics: the very low frequency of PGD^B and p^a alleles; the existence of two rare PGM variants at the PGM₂ locus, typical PGM ₂ ^6Pyg (4.2%) and PGM ₂ ⁹ (0.2%); the high frequency of the p^r allele (10.8%) and CA _II ² (8.22%) and ESD² genes (18.4%). Furthermore, at the G6PD locus four distinct alleles have been found: the negroid GDA-(4%) and GdA+(16%), the common GdB+(79.2%)-,and the rare Gd+^{Ibadan Austin} (0.7%). Cholinesterase typings disclosed the presence of the uncommon E ₁ ^f and E ₁ ^s genes distributed within a single breeding unit. The results are compared with other data previously reported on South African Khoisan and some Negroid populations; the particular genetic background of Pygmies is discussed.Otherwise known as Bi Aka