Subtyping of human red cell phosphoglucomutase locus 1 (PGM1) polymorphism: a third PGM1(1) allele common among Twa Pygmies from North Rwanda.

Seventy-eight Twa Pygmies from North Rwanda have been subtyped by acid starch gel electrophoresis for the polymorphism at the phosphoglucomutase locus 1 (PGM1). A third common PGM1(1) allele that has been named PGM1(1Twa) was detected in heterozygous association with both PGM1(1S) and PGM1(1F) alleles. The PGM1(1Twa) product is faster than those of the other two PGM1(1) alleles and has the same electrophoretic mobility as the rare PGM1(6) enzyme. The frequency of PGM1(1Twa) was found to be 0.45.