Population genetic study in ten endogamous groups of West Bengal, India

Ten endogamous population groups of West Bengal (India)--Rabhas, Garos, Mechs, Rajbanshis, Jalia Kaibartas, Bagdis, Lodhas, Mundas, Brahmins, Vaidyas--have been typed for twelve polymorphic systems: ABO, Gm, Km, Hp, Cp, Tf, Alb, Hb, aP, EsD, AK and PGM1. The results are compared with those obtained on other Indian populations. Serological and anthropometric data, which have been included into population comparisons, reveal a considerable genetic variability of the groups under study. This variability is obviously connected with the population history of West Bengal.     

Gene differentiation among ten endogamous groups of West Bengal, India

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.     

Genetic distance and gene diversity among ten endogamous groups in Chhattisgarh,Central India

A genetic survey has been conducted among the Rawats and Telis, two endogamous caste populations of Chhattisgarh, Central India. Using the gene frequency data for three genetic loci, genetic distance among ten population groups have been calculated. The gene differentiation among these population groups is only about 2 per cent.     

Genetic polymorphism analysis among nine endogamous population groups of Maharashtra,India

The present paper reports results of analysis of 14 genetic marker systems-ABO, MN, Rh, Hp, Tf, Cp, Alb, AcPH, PGM, LDH, MDH, Est-D, Hb and G-6-PD studied on a number of subjects of 9 endogamous groups of Maharashtra: Bhils, Katkaris and Pawaras, (all tribal groups); Deshastha Rigvedi and Chitpavan (two Brahmin groups); Nava Budhas (a scheduled caste); Chandrasenya Kayastha Prabhu and Marathas (two middle caste groups); and Parsis a migrant group from west Asia. Analysis of heterogeneity of gene frequencies reveal considerable heterogeneity for most of the loci among these groups.     

Genetic distance analysis among nine endogamous population groups of Maharashtra,India

Genetic distance analysis based on 16 biochemical markers, following Nei's distance measure has been performed on nine endogamous groups of Maharashtra: Nava Budha, Maratha, Deshastha Rigvedi Brahmin, Chitpavan Brahmin, Chandrasenya Kayastha Prabhu, Parsis, Bhil, Pawara and Katkari. The distances between these groups are small as compared to the within group heterogeneity. The average heterozygosity per gene per locus is high for all the populations (in the range of 20–22%). The observed clusterings among these nine groups, in general, are compatible with the known ethnic history of Maharashtra.     

Asymmetry and diversity of dermatoglyphic traits: population comparison in five endogamous groups of West Bengal, India

Five different endogamous populations encompassing the main social ranks in the caste hierarchy of West Bengal, India were analyzed. To compare variability in populations with contrasting ethnohistorical backgrounds, analysis of variance, Scheffe's test and cluster analysis were performed, as based on dermatoglyphic variables, namely, 22 quantitative traits and 36 indices of diversity and asymmetry. The present study reveals that: 1. Overall disparities among the 5 populations are expressed only in finger ridge counts on the Ist and Vth digits and PII, in a-b ridge counts, in endings of main lines A and D, and in MLI on the palms; 2. Heterogeneity is greater in fluctuating asymmetry than in directional asymmetry; 3. There is a greater heterogeneity in the 22 quantitative traits than in the 36 indices of diversity and asymmetry, with females contributing more than the males; 4. The highest contribution to population variation is by Lodha among five populations; 5. Inter-group variations are homogeneous in most of the variables, which does not correspond with the relationships to caste hierarchy of these populations; 6. The dendrograms based on dermatoglyphic variables demonstrate that the traditional grouping of Indian populations, based on caste hierarchy, may not be a reflection of their genetic origin, in that the pattern of clustering corresponded best with the known ethnohistorical records of the studied populations; 7. Hence, dermatoglyphic affinities may prove quite useful in tracing the ethnohistorical background of populations.     

The distribution of the group specific component (Gc) in four endogamous groups of Punjab, North India

The paper reports the distribution of group specific component (Gc) types among four endogamous groups of Punjab: Jat Sikh, Khatri, Ramgarhia, and Ramdasia. A total of 418 individuals were tested for this polymorphism. The frequency of Gc1 alleles ranges between 0.7056 and 0.7636. These frequencies are compared with those obtained in other Indian populations.     

Inbreeding among three endogamous groups in a multicaste village of Andhra Pradesh,India

Abstract

The frequency of consanguineous marriages was studied in three endogamous castes, the Reddis (Kapus), Yadavas (Gollas), and Madigas of Marripadu village in South India. Inbreeding was higher among the Yadavas (Gollas) (0.0312) and Madigas (0.0271) than among the Reddis (Kapus) (0.0154) due to their higher frequencies of uncle‐niece marriages.     

Minimal sharing of Y-chromosome STR haplotypes among five endogamous population groups from western and southwestern India

We attempt to address the issue of genetic variation and the pattern of male gene flow among and between five Indian population groups of two different geographic and linguistic affiliations using Y-chromosome markers. We studied 221 males at three Y-chromosome biallelic loci and 184 males for the five Y-chromosome STRs. We observed 111 Y-chromosome STR haplotypes. An analysis of molecular variance (AMOVA) based on Y-chromosome STRs showed that the variation observed between the population groups belonging to two major regions (western and southwestern India) was 0.17%, which was significantly lower than the level of genetic variance among the five populations (0.59%) considered as a single group. Combined haplotype analysis of the five STRs and the biallelic locus 92R7 revealed minimal sharing of haplotypes among these five ethnic groups, irrespective of the similar origin of the linguistic and geographic affiliations; this minimal sharing indicates restricted male gene flow. As a consequence, most of the haplotypes were population specific. Network analysis showed that the haplotypes, which were shared between the populations, seem to have originated from different mutational pathways at different loci. Biallelic markers showed that all five ethnic groups have a similar ancestral origin despite their geographic and linguistic diversity.     

Genetic variation of five blood group polymorphisms in ten populations of Assam,India

Six Mongoloid and four Caucasoid populations of Assam, India, were examined for A₁A₂BO, Rhesus, Duffy and Diego blood groups. The distribution of their phenotypes and allele frequencies are presented. In the perspective of the ethnographic background, the results have been discussed in terms of genetic variability among these populations and probable reasons for its existence. The major groups, namely Caucasoids and Mongoloids, appear to form two separate groups in terms of these blood groups, though evidence is there to suggest intermixture.     

Distribution of Gm and Km allotypes among ten populations of Assam, India

Serum samples from ten endogamous populations of Assam, India-Brahmins, Kalitas, Kaibartas, Muslims, Ahoms, Karbis, Kacharis, Sonowals, Chutiyas, and Rajbanshis-were typed for G1m (1, 2, 3, 17), G3m (5, 10, 11, 13, 14, 15, 16, 21, 26), and Km (1). Among Brahmins, Kalitas, Kaibartas, Muslims, Ahoms, Sonowals, Chutiyas, and Rajbanshis, five different Gm haplotypes were found: Gm1,17;21,26; Gm1,17;10,11,13,15,16; Gm1,2,17;21,26; Gm1,3;5,10,11,13,14,26; and Gm3;5,10,11,13,14,26. Kacharis and Karbis show only four of these haplotypes: Gm3;5,10,11,13,14,26 is absent among them. The intergroup variability in the distribution of these haplotypes is considerable, which can be explained by the ethnohistory of these populations. Genetic distance analysis, in which five Chinese population samples were included, revealed the existence of three main clusters: 1) North and Central Chinese; 2) Kalitas, Kaibartas, Chutiyas, Rajbanshis, Muslims, and Brahmins; and 3) Ahoms, Sonowals, Kacharis, South Chinese, and Karbis. The clusters suggest some genetic relation between these four Assamese populations and South Chinese, which is again understandable considering the ethnohistory of the populations of Northeast India. In the Km system, too, a remarkable variability is seen in distribution of phenotype and allele frequency.     

Predominance of the haemoglobin E gene in a Mongoloid population in Assam (India).

A high frequency of the haemoglobin E gene (HbbetaE) had been found in 1972 in the Ahom, a mongoloid population in Upper Assam. The present study confirms frequencies between 0.3 and 0.35 for this population in a larger sample from different areas. An even higher frequency near 0.5 was found in the Kachari of Upper Assam, a tribe of the tibetoburman Bodo group. HbbetaE frequencies in these groups are compared with the frequencies in the general Assamese population and the austroasiatic Khasi of Meghalaya.     

Inbreeding among endogamous groups in three multicaste villages of Srikakulam district,Andhra Pradesh,India

Abstract

In the present paper 702 families have been studied belonging to different endogamous groups in three multicaste villages of Srikakulam District, Andhra Pradesh. It is observed that 33.76 per cent of families are consanguineous marriages. With regard to the types of marriages, 12.11 per cent are uncle‐niece; 14.10 per cent are matrilateral cross‐cousins; 5.84 per cent are patrilateral cross‐cousins; 0.57 per cent are first cousins once removed, and 1.14 per cent are second cousins. There are only six couples (0.86 per cent) in intercaste marriages. The coefficient of inbreeding for autosomal and sex‐linked genes, 0.045 and 0.059, respectively, for Chakalis which are higher than Kalingas (F = 0.03; F1 = 0.038), Segidis (F = 0.031; F1 = 0.041), Velamas (F = 0.026; F1 = 0.036), Vysyas (F = 0.027; F1 = 0.034), Malas (F = 0.017; F1 = 0.026), and others (F = 0.026; F1 = 0.032). The t‐tests for mean marriage distances are statistically significant among all castes, but chi‐squares for intergroup difference of consanguineous and nonconsanguineous marriages are statistically significant only among Kalingas and Chakalis, Vysyas and Chakalis, and Malas and Chakalis.     

Microsatellite variation at 24 STR loci in three endogamous groups of Uttar Pradesh,India

We have studied variation at 24 microsatellite markers among 50 individuals from each of three endogamous groups, Bhargavas, Chaturvedis, and non-Bhargava, non-Chaturvedi Brahmins of Uttar Pradesh, India. The number of alleles at the loci tested varied from 4 to 11, with an average of 6 at each locus. Heterozygosity was found to be quite high at all loci in the three subpopulations. It varied between 0.44 to 0.84 among Bhargavas (average 0.6510), 0.44 to 0.80 among Chaturvedis (average 0.6633 +/-), and 0.42 to 0.85 among Brahmins (average 6.694 +/-). Hardy-Weinberg equilibrium analysis revealed that these populations are under genetic equilibrium at almost all the loci tested. Comparisons of allele frequency between Bhargavas and Chaturvedis showed that they differed significantly at 14 short tandem repeat (STR) markers (p < 0.001), while Chaturvedis and Brahmins differed at 6 (p < 0.05) and Brahmins and Bhargavas at 8 (p < 0.05). Average F(IS) and F(ST) for the 24 STR markers was -0.02 and 0.013, respectively. We used both un-weighted pair group with arithmetic mean and principal components analysis to evaluate genetic distances among the three groups. Our results revealed that although there were differences at particular allele frequencies between Bhargavas vs. Brahmins, Bhargavas vs. Chaturvedis, and Brahmins vs. Chaturvedis, these differences were not statistically significant when combined over all 24 STR markers between Chaturvedis vs. Brahmins and Bhargavas vs. Brahmins. The genetic distance analysis revealed that Bhargavas are slightly apart from the other two populations.     

Anthropological studies in Assam, India

Four Assamese caste groups--Jogis, Hiras, Kumars and Kaibartas--have been analysed for the distribution of anthropometric and dermatoglyphic traits as well as for the distribution of ABO blood groups and PTC taste sensitivity. The differences among these four caste groups are statistically mostly significant, which can be connected with the history of these groups and their genetic isolation from each other.     

Inbreeding effects on palmar dermatoglyphic characters in three endogamous social groups of West Bengal,India

The present study reports inbreeding effects on mean palmar dermatoglyphic characteristics: triradial count on palm, maximal atd angle, adt angle, td ridge count, ab ridge count, main line index (MLI) and ab ridge breadth. Samples were drawn from adult males belonging to three endogamous sections representing Hindu caste Telaga of Kharagpur (West Midnapore), Ansari Muslims of Nandigram (East Midnapore) and Sheik-Sunni Muslims of Braddhaman in West Bengal, India. Consistent trend of higher mean triradial number, adt angle, and lower mean td ridge count, ab ridge count, and ab ridge breadth was observed in inbred sections compared to their non-inbred relatives in three social groups.