Advanced Statistical Methods in Biometric Research.

Apolipoprotein E (APOE = gene, apoE = protein) plays a central role in plasma lipoprotein metabolism and in lipid transport within tissues. The APOE shows a genetic polymorphism determined by three common alleles, APOE*2, APOE*3, APOE*4 and the product of the three alleles differs in several functional properties. APOE is involved in the development of certain pathological conditions. In particular, the APOE*4 allele is a risk factor for susceptibility to coronary artery disease (CAD) and Alzheimer's Disease (AD). In the present study we analyzed the APOE allele distribution in the world. The APOE*3 is the most frequent in all the human groups, especially in populations with a long-established agricultural economy like those of the Mediterranean basin (0.849-0.898). The frequency of APOE*4, the ancestral allele, remains higher in populations like Pygmies (0.407) and Khoi San (0.370), aborigines of Malaysia (0.240) and Australia (0.260), Papuans (0.368), some Native Americans (0.280), and Lapps (0.310) where an economy of foraging still exists, or food supply is (or was until the recent past) scarce and sporadically available. The APOE*2 frequency fluctuates with no apparent trend (0.145-0.02) and is absent in Native Americans. We suggest that the APOE*4, based on some functional properties it has and on its distribution among human populations, could be identified as a 'thrifty' allele. The exposure of APOE*4 to the contemporary environmental conditions (Western diet, longer lifespans) could have rendered it a susceptibility allele for CAD and AD. The absence of the association of APOE*4 with CAD and AD in Sub-Saharan Africans, and its presence in African Americans, seems to confirm this hypothesis.

https://onlinelibrary.wiley.com/doi/pdf/10.1046/j.1469-1809.1999.6340301.x

Apolipoprotein E (APOE) allele distribution in the world. Is APOE*4 a 'thrifty' allele?

https://www.bmj.com/content/bmj/1/6059/515.3.full.pdf

Handbook of Enzyme Electrophoresis in Human Genetics

Handbook of enzyme electrophoresis in human genetics

Blood group variants are characteristic of population groups, and can show conspicuous geographic patterns. Interest in the global prevalence of the Duffy blood group variants is multidisciplinary, but of particular importance to malariologists due to the resistance generally conferred by the Duffy-negative phenotype against Plasmodium vivax infection. Here we collate an extensive geo-database of surveys, forming the evidence-base for a multi-locus Bayesian geostatistical model to generate global frequency maps of the common Duffy alleles to refine the global cartography of the common Duffy variants. We show that the most prevalent allele globally was FY*A, while across sub- saharan Africa the predominant allele was the silent FY*B ES variant, commonly reaching fixation across stretches of the continent. The maps presented not only represent the first spatially and genetically comprehensive description of variation at this locus, but also constitute an advance towards understanding the transmission patterns of the neglected P. vivax malaria parasite.

/pdf/the-global-distribution-of-the-duffy-blood-group-12h1nppoy6.pdf

The global distribution of the Duffy blood group.

People of India: An investigation of biological variability in ecological, ethno-economic, and linguistic groups

Previous studies have reported a high incidence of hemoglobin E (HbE) in Northeast Indian populations. In the present study 10 endogamous populations of Assam belonging to two racial groups, Caucasoid and Mongoloid, were examined. The frequency of HbE gene (Hb βE) in the Caucasoid caste populations is around 0.1, whereas the gene is highly prevalent in the Mongoloid populations, frequencies ranging between 0.2 and 0.6. Predominance of Hb βE in the Tibeto-Burman speakers is contrary to observations made in Southeast Asia, where an association between Austro-Asiatic speakers and high prevalence of HbE exist. The highest occurrence of the gene in this area, which is on the far end of the proposed centre of distribution in Northern Kampuchea and Northeast Thailand, is also a deviation from the expected pattern of gene distribution. It is speculated that Hb βE in the Tibeto-Burman populations of Assam arose by an independent mutation which contributed to the high frequencies of Hb βE in the Northeast Indian populations.

Hemoglobin E Distribution in Ten Endogamous Population Groups of Assam, India

Genetic polymorphisms for six blood groups, three red cell enzymes, three serum proteins, and hemoglobin were examined in sixteen central Indian tribal populations. Nine of the tribes belonged to Orissa, five to Madhya Pradesh, and two to Maharashtra. Eleven tribes spoke the Dravidian language, three Indo-Ayran, and two the language of the Austro-Asiatic families. The population structure of these tribal populations was analyzed at the inter- and intrastate and linguistic levels, using data for 13 genetic systems (38 alleles or haplotypes). Nine of the 13 loci showed significant heterogeneity in the 16 tribes, and the pattern of heterogeneity was also discernible in the different states and in the Dravidian-speaking tribes. As expected, the extent of genetic differentiation or gene diversity was the highest so far reported from central India. The mean FIS and HS for each locus in the different state, linguistic, and total tribal groups were consistently higher than the FST and GST values, respectively, showing that the genetic structure of each tribe is highly influenced by inbreeding. In a genetic affinity analysis by genetic distance the Indo-Aryan and Austro-Asiatic language groups showed little affinity with each other, although there was some tendency toward geographic affinity. The present analysis indicates that, in addition to genetic drift, gene flow, and selection, the genetic structure of the populations of central India is also highly influenced by sociocultural adaptation and inbreeding.

Population structure and genetic differentiation among 16 tribal populations of central India.

The distribution of genetical, morphological, and behavioural traits among the peoples of Indian region: Bangladesh, Bhutan, India, Maldives, Nepal, Pakistan, Sri Lanka

Ten endogamous populations of West Bengal, India have been surveyed for genetic variation in 12 systems. These populations encompass all social ranks in the caste hierarchy and cover almost the entire geographic area of the state. Gene diversity analysis suggests that these groups exhibit significant allele frequency variation at all but three loci. The overall genetic difference is not, however, in accord with the classification based on caste. Two low-ranking scheduled caste groups are, in fact, in close proximity with the high-caste ones, suggesting evidence of past generations of gene flow among them. Three different clusters of groups emerge from the present data, providing support for the anthropologic assertion that in Bengal Proto-Australoid, Caucasoid, and Mongoloid racial elements generally coexist. However, these three components are not uniformly present in all groups. Geographic separation of the groups is a strong determinant of the gene differentiation that exists among these populations.

Hubert Walter

Papers

People of India: An investigation of biological variability in ecological, ethno-economic, and linguistic groups

Hemoglobin E Distribution in Ten Endogamous Population Groups of Assam, India

Population structure and genetic differentiation among 16 tribal populations of central India.

The distribution of genetical, morphological, and behavioural traits among the peoples of Indian region: Bangladesh, Bhutan, India, Maldives, Nepal, Pakistan, Sri Lanka

Gene differentiation among ten endogamous groups of West Bengal, India.