Class I HLA antigens in two long-separated populations: Melanesians and South Amerinds

Class I HLA antigens have been compared in 5,835 Melanesians of Papua New Guinea and 2,028 Amerindians of South America. The sample includes 50 PNGMel ethnolinguistic groups and 22 SAmlnd groups. Both carry 15 serologically defined antigens and an undefined C allele. Except for A2 in Papua New Guinea and Cwl in South America, these antigens are widely distributed in their respective populations. Nine (A2 and A24, B39, B60 and B62, and Cwl, Cw3, Cw4, and Cw7) are common to both. This commonality suggests that these two populations derive from an ancestral population with less polymorphism than modern East Asians. In both populations several theoretically possible haplotypes were absent, and other haplo-types were in positive disequilibrium in both. The parallels in disequilibria suggest that haplotypes are subject to selective forces acting on the level of allelic interaction. Based on three locus haplotype frequencies, the PNGMel groups form five clusters with internally typical linguistic and geographic characteristics and a miscellaneous category, but Samlnd groups show no cluster. © 1995 Wiley-Liss, Inc.     

Altitude,language, and class I HLA allele frequencies in Papua New Guinea

Class I HLA gene frequencies show considerable variation over short geographical distances in Papua New Guinea. Hypotheses to account for this invoke natural selection, population structure, the pattern of population movement, or past demographic changes. To determine the role of the various factors in shaping this distribution, we have studied correlations between HLA-based genetic distances, geographical distances, altitude, and linguistic differences in Papua New Guinea. Linguistic differences at the family or stock level within the Trans-New Guinea Phylum generally correspond to genetic differences. However, on the basis of their HLA gene frequencies, speakers of Austronesian (AN) languages do not form a distinct group of populations. Linguistic variation and spatial autocorrelation do not fully account for the altitudinal cline differences noted in gene frequencies, particularly at the HLA-A locus. We propose that the distribution of HLA gene frequencies in Papua New Guinea is partially under the control of selection operating differentially along the altitude gradient. © 1994 Wiley-Liss, Inc.     

Gm and Inv (Km) studies of melanesian people on the Huon Peninsula in northeast Papua New Guinea: Polymorphism for a Gm1,5,10,11,13,14,17,21,26 haplotype

Blood samples from 448 people living in six villages in the Huon Peninsula in northeast Papua, New Guinea, were tested for Gm(1,2,3,5,6,10,11,13,14,17,21,24,26) and Inv(1) [Km(1)]. All the people are non-Austronesian (NAN) speakers. As expected, there was a low frequency of the Gm^{1,3,5,10,11,13,14,26} haplotype, but in contradiction to expectations there was a complete absence of the Gm^1,2,17,21,26 haplotype. In addition, samples from people in one village (Yupna) and probably those for two other villages (Irumu 13 and 14) have the rare haplotype Gm^{1,5,10,11,13,14,21,26} at polymorphic frequencies. Two samples from people living in Yupna had the rare phenotype Gm(1,3,17,21,26), indicating the presence of any one of several rare haplotypes that had been observed in other populations. These are discussed.     

Malocclusion in the Kwaio, a Melanesian group on Malaita, Solomon Islands

In the present investigation, a number of occlusal variables which contribute to malocclusion were quantified among the Kwaio people of Malaita, Solomon Islands. Angle classification, overjet, overbite, openbite, crossbite, rotation, crowding, and spacing were assessed from dental casts of 180 persons (94 males, 86 females) who had complete permanent dentitions anterior to the first molar. Males had significantly more overjet and mandibular incisor crowding than females, and significantly less posterior openbite and mandibular canine-premolar spacing. The frequency of openbite, rotation of maxillary teeth, and crowding of anterior teeth increased with advancing age. The frequency of posterior crowding decreased after age 30. Spacing, in general, increased with advancing age. In the distribution of the Angle classes of occlusion, the Kwaio resembled Australian aborigines living in technologically primitive circumstances.