The genetic demography of the Gainj of Papua New Guinea. I. Local differentiation of blood group, red cell enzyme, and serum protein allele frequencies.

Allele frequencies are reported for 19 blood group, red cell enzyme, and serum protein loci (ABO, Rh, MN, Hb-A, LDH-A, LDH-B, SOD, PGM-1, PGM-2, 6PGD, GPT, ESD, ADA, ACP, PGK, MDH, Alb, Hp, and Tf) determined from 310 blood samples collected among the Gainj, a small population of tribal horticulturalists from highland Papua New Guniea. Fourteen of these loci display genetic variants, and ten of them are sufficiently polymorphic to permit a preliminary analysis of Gainj population structure. Patterns of variation among subdivisions of the population are analyzed using an approach analogous to a multivariate analysis of variance with unbalanced design, and weighted genetic distances are extracted from the results. The distance analysis indicates that patterns of genetic variation within this population reflect the geographical distribution of subdivisions, as well as subdivision size and movement among subdivisions. A parallel analysis of the Gainj and two other tribal groups from highland New Guinea, the Murapin Enga and the Simbai Valley Maring, suggests that the Gainj are both genetically divergent from neighboring populations and internally highly differentiated.