The ABH secretor status of Kalahari Bushmen.
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Black or African American↗
Biomedical subjects
T Jenkins
Publications and source records attributed to T Jenkins.
Ability to taste phenylthiocarbamide among Kalahari Bushmen and Southern Bantu.
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Adolescent↗
The Njinga of Angola: a serogenetic study.
The Njinga, a matrilineal kiMbundu-speaking Negro people of northern Angola, inhabited the coast near Luanda during the sixteenth century, and were driven inland by Portuguese expansion subsequently. There is no evidence from the present sterogenetic study that they have received any appreciable contribution of Caucasoid genes. Nor is there any evidence of San ('Bushman') admixture apart from a moderate frequency of Gm; their genetic profile and their anthroposcopic traits disclose a greater similarity to West African than to Southern African Negroes. The present study confirms previous findings on the ABO, MNSs, Kell, Duffy, erythrocyte acid phosphatase, adenosine deaminase and adenylate kinase systems, and contributes the first account of the peptidase A, B, C and D, first and second locus phosphoglucomutase, glucose-6-phosphate dehydrogenase, esterase D, haptoglobin, transferrin, Gm and Inv systems in the Njinga.
ABO Blood-Group System↗
Persistent high intestinal lactase activity in Papua New Guinea. Lactose absorption curves in two populations.
Thirty adolescent males, aged 16-19 years, all of Huli, Mendi or Dunai descent, sampled at Tari in Southern Highlands of Papua New Guinea, and 29 children aged between 9 and 15 years, all speakers of Daga and sampled at Agaun in the Milne Bay Province, have been tested for persistent high intestinal lactase activity. Three persons at Tari and five at Agaun were found to be lactose absorbers. There is reasonably convincing evidence that all five absorbers at Agaun descend from a common ancestor five generations ago, but there is no such suggestion for those tested at Tari. Gene flow from Caucasoids who penetrated both areas is possible. The presence of lactose absorbers in peoples who are not traditional users of fresh milk suggests that the culture historical hypothesis may not give a completely adequate explanation for the establishment and conservation of the lactose polymorphism in man.
Adolescent↗
Sero-genetic studies on the Basters of Rehoboth, South West Africa/Namibia.
The Basters of Rehoboth in South West Africa/Namibia arose by hybridization between Caucasoids and Khoi ('Hottentots') in the northern Cape Province of South Africa during the eighteenth and nineteenth centuries, followed by migration of a single well-defined party to Rehoboth and the consolidation of an ethnocentric nation there. Although there has been some gene flow into the population during the twentieth century, the present sero-genetic study contributes further evidence for the hypothesis of Fisher (1913) that each ancestral strain had furnished an equal contribution to the population.
ABO Blood-Group System↗
Serogenetic studies on the Daga of the interior of the mainland of Milne Bay Province, Papua New Guinea.
The Daga people of Milne Bay, the easternmost Province of Papua New Guinea, occupy an upland area but do extend to the coast. Linguistically they are Papuan and, unlike their Austronesian-speaking neighbours, they appear originally to have been an exclusively inland people. They have been in contact with missionaries and miners since the turn of the century, and genetic evidence of Caucasoid gene flow may be present in the finding of several lactose absorbers (reported elsewhere). They are the first non-Australian population in whom the second carbonic locus allele CA4II has been detected, which may indicate either recent gene flow from Australian aborigine or lend additional support to the suggestion that there was Australian contact with Papua before the coming of the Europeans. For the rest, their gene-marker profile is fairly typical of a non-highland population of New Guinea, though the low frequency of hereditary ovalocytosis tends to confirm their inland origins.
Alleles↗
Serogenetic studies on the inhabitants of Tristan da Cunha.
The inhabitants of Tristan da Cunha, a remote island in the South Atlantic, number about 300 and are direct descendants of a small number of individuals who settled there in the first half of the nineteenth century. Some serogenetic studies were carried out on the islanders when they were evacuated to England in 1961 but 160 individuals have now been tested for a much wider range of gene markers. No variation was found at 15 loci while considerable variation was encountered at 12 loci. In particular, the high frequency of A1 and the complete absence of A2 in the ABO system was confirmed; the high frequency of Ro (cDe) in the Rhesus system and GdA, an allele at the G6PD locus, as well as the presence of three haplotypes in the Gm system (Gm1,5,6,14,17, Gm1,5,6,17 and Gm1,5,13,14,17) confirm the known historical origin of the women founders who came from St Helena. Although the degree of inbreeding is high there is no significant deficiency of heterozygotes in the eight informative systems.
Adolescent↗
Serogenetic and haematological studies on the Kgalagadi of Botswana.
A sample of Kgalagadi, Negro speakers of a Sotho/Tswana Bantu language, inhabitants of Botswana, have been investigated for variation in 27 gene-marker systems and for haematological status and the presence of intestinal parasites. They have been found to show indications of genetic affinity both to the other Sotho/Tswana and to the Mbanderu divisions of the Herero, a Bantu-speaking Negro people of Namibia. The latter affinity appears the closer. Although the historical connection between the peoples seems unlikely on cultural and oral-historical grounds, it is not impossible, given the shallow depth of the oral history of the Herero and the consequent doubts about the antiquity of their present cultural system. Nothing in the genetic profile of the Kgalagadi contradicts the claim that they represent a very early, and perhaps the first, wave of Negro immigration into southern Africa. They have been investigated for intestinal parasites and haematological status as well. They appear to be haematologically healthy, and to possess only the narrow range of parasites previously found in the Kalahari Desert, apart from one subject in whom Hymenolepis nana (Dwarf tapeworm) was found.
Adolescent↗
Mitochondrial DNA polymorphisms in Negroid populations from Namibia: new light on the origins of the Dama, Herero and Ambo.
Mitochondrial DNA (mtDNA) polymorphisms were investigated in the Herero, Dama and Ambo Negroid groups from Namibia, using the restriction enzymes HpaI, BamHI, HaeII, MspI, AvaII and HincII. Although the Dama presently speak a Hottentot language, Nama, their mtDNA pool closely resembles that found in the Herero who are western-Bantu speakers, suggesting that these groups may be derived from the same female ancestor. Both the Dama and the Herero have a high frequency of mtDNA type 21-2 (2-1-1-1-2-2), found at frequencies of 32.6% and 50.0%, respectively, compared to 4.5% in the Ambo. In addition, the 'Negroid-like' types 2-2 (3-1-1-1-3-2) and 7-2 (3-1-1-1-1-2), found at frequencies of 13.5% and 54.5%, respectively, in the Ambo, are rarely found in the Dama and Herero. This suggests that the Ambo have different origins from the Herero and Dama; they appear to be more closely related to southeastern Bantu-speakers than to southwestern Bantu-speakers.
Black People↗
Issues in human GenEthics.
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Ethics, Medical↗
The Y-specific p21A1/TaqI polymorphism occurs in four major population Oroups.
The p21A1/TaqI polymorphism was studied in 904 individuals in 23 African population groups, encompassing the Caucasoid, Negroid, Khoisan and Pygmy populations. The frequency of the polymorphism was higher than previously reported, with the rarer allele occurring at frequencies ranging up to 0.41. No distinct trends in population frequency were observed, suggesting that the polymorphism is of little value in anthropological population studies. The existence of several TaqI mutations, in both time and position within the repeat unit, is indicated.
Africa↗
The Y-specific pDP31 rearrangement polymorphism in southern African populations.
The pDP31 rearrangement polymorphism was studied in 353 individuals encompassing the southern African Khoisan, Negroid and Caucasoid populations. The three alleles representing the ancestral (unrearranged) DNA configuration, the duplication, and the triplication were detected in most of the populations studied. The duplication occurred at higher frequencies in Caucasoid groups than in African populations, whilst the triplication was most common in Negroids. Populations of mixed ancestry exhibited allele frequencies closer to Caucasoids than to Negroids, in accordance with their historical origins.
Alleles↗
Study of 30 DNA markers in three southern African populations.
Thirty anonymous DNA markers were investigated in Southern African Caucasoid, Negroid and San populations. Sixteen of these are new markers that were developed in our laboratory; the remainder are closely linked to the cystic fibrosis locus on chromosome 7. Average heterozygosity in the Caucasoid and Negroid populations was calculated at the loci identified by each of the anonymous probes, using two approaches, and was found to be .0020 and .0030 for the Caucasoid population and .0023 and .0025 for the Negroid population. Variation between populations (measured by FST) and between markers was calculated from allele frequency data gathered for all markers in the three populations. Significant differences in allele frequency between the populations were observed for the cystic fibrosis markers MET D, MET H and 7C22, with little or no variation observed in the Negroid and San populations. Mean heterozygosity (D) was found to be considerably lower in San (.250) than in Caucasoid (.373) and Negroid populations (.0320) and possible explanations for this are provided. The smallest genetic distance (60 x 10(-3)) was found between the Negroid and San populations, and the greatest distance between the Caucasoid and San populations (167 x 10(-3)).
Africa, Southern↗
Medical genetics today.
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Chromosome Aberrations↗