GM and KM allotypes in eight tribal populations of Madyha Pradesh and Orissa, India.

Serum samples from eight endogamous Indian tribal populations of Madhya Pradesh (Dhurwa, Halba, Bhatra, Muria, Maria) and Orissa (Deshia Khond, Binjhal, Kisan) with a total of n = 731 unrelated individuals were typed for G1M (1,2,3,17), G3M (5,10,11,13,14,15,16,21, 26), and KM (1). In seven of these populations five different GM haplotypes were found: GM* 1,17;21,26; GM* 1,17;10,11,13,15,16; GM* 1,2, 17;21,26; GM* 1,3;5,10,11,13,14,26; and GM* 3;5,10,11,13,14,26. In the Kisan sample the haplotype GM* 1,2,17;21,26 is absent. The intergroup variability in the distribution of these haplotypes is considerable and statistically highly significant. The reasons for that can be attributed to the ethnohistory and to the genetic isolation of these eight endogamous tribal populations. The GM haplotype distribution pattern of all these groups is quite different from that of the non-tribal populations of India, whereas it is in good agreement with that of the so far tested other tribal populations from India. This can be explained by different origin and history of the Indian tribal and non-tribal populations. In the KM system, too, remarkable variability is seen in the distribution of phenotype and allele frequencies among the eight tribal populations under study.

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

Genetic epidemiology of blood pressure in two Indian populations: some lessons.

A genetic epidemiological study of blood pressure was conducted in two contrasting populations: the Marwaris of Calcutta and the Hindu middle-caste agriculturists of Digha. The Marwaris are heavier and significantly more obese than the agriculturists. The prevalence of hypertension among the Marwaris (17%) is more than tenfold higher than that among the agriculturists (1.4%). Genetic analysis of blood pressure data using a path model indicates that blood pressure levels (adjusted and standardized for age, gender, education level, and disease status) are primarily determined by environmental factors, as measured by their effects on anthropometric characters. The observed familial resemblance of blood pressure levels in the two populations is primarily due to cultural rather than genetic inheritance. Genetic and familial effects on covariation between anthropometric measures of obesity and blood pressure levels are perhaps so strong that there is no residual genetic heritability of adjusted blood pressure levels.

Spatial autocorrelation analysis reveals that A, B and O allele frequency surfaces on the Indian subcontinent are highly fractured.

Spatial autocorrelation analysis performed on published data pertaining to caste and tribal populations of the Indian subcontinent has revealed that the surfaces of A, B and O allele frequencies are highly fractured. The only significant spatial autocorrelation was observed in respect of the A allele frequency among caste populations.

Biology of Saryupari Brahmins of Chhattisgarh, central India.

In July-November, 1986, Saryupari Brahmins of Chhattisgarh (Central India) have been investigated for the distribution of ABO blood groups, Rh factor, ABH secretion, PTC taste sensitivity and seven morphological traits. The important findings in brief are as follows: 1. The frequency of O blood group is slightly dominant (38.91%) and gene frequency exhibit r > q > p pattern. Statistical analysis (D/sigma = 0.5447) show that the population is in genetic equilibrium. 2. Estimation of the expected rate of erythroblastosis foetalis occurred in this population is calculated to be 8-16 cases in every 10,000 pregnancies. 3. High incidence (53.82%) of non-secretors of ABH substances in saliva suggest that this group may belong to Caucasoid stock. 4. The ability to taste the chemical PTC has a high frequency (61.81%) in this group. 5. R/L type of handclasping (58.15%), leg folding (65.38%) and L/R type of arm folding (58.93%) is dominant. L-type of handedness (5.48%) is moderately high. 6. Tongue rollers (93.28%) and folders (53.77%) are more among them. 7. Free type of ear lobe (68.68%) is the common feature in this population. 8. The above observations were compared in details with other Brahmin populations reported from India with special reference to the descendant groups residing in Madhya Pradesh (Central India). Furthermore, the results obtained on growth studies, and dermatoglyphic studies (palm and sole) from our published literature were also included so as to have some idea on the genetical, behavioural, dermatoglyphic and growth norms of this group.

A case-control study of reproductive risk factors associated with cervical cancer.

Using the logistic-regression technique, a hospital-based case-control study of 177 married women with invasive squamous-cell cervical cancer and 149 hospital-visiting controls enabled evaluation of selected reproductive factors as risks. Early age at marriage was found to be the single best predictor of the disease status. However, those who married late but gave birth to a large number of children were generally found to be suffering from cervical cancer. The results support the hypothesis that it is not so much parity per se that enhances the risk, but the rapidity of multiple pregnancies that matters. Logistic analysis also revealed the independent influence of birth interval on the risk of cervical cancer. These findings warrant serious consideration in future studies, given the obvious implications for prevention. Other implications for the prevention of cervical cancer are briefly discussed.

A case cancer control study of reproductive in breast cancer.

The role of reproductive factors, such as, parity, age at menarche, age at first child's birth have been investigated in a hospital based case-control study, for their independent as well as combined influences on the incidence of female breast cancer. The study indicates that except for parity, these factors have no influence on the age at onset of the disease. Parity is positively correlated with age at onset. The patient and the control groups were found to be similar in respect of age at first child's birth and age at menarche, but the patient group was significantly lower both in parity and age at onset of the disease. Both these factors are negatively associated with the incidence of breast cancer. Therefore, preventive action should be focussed on young women with low parity.

An epidemiological study of blood pressure and lipid levels among Marwaris of Calcutta, India.

This population based study was conducted among the Marwaris of Calcutta, India. A total of 1,096 individuals from 151 randomly selected families were studied. Mean blood pressures were high. About 17% of the population was hypertensive, i.e., systolic blood pressure > 160 mm Hg and/or diastolic blood pressure > 95 mm Hg. The mean value of the ratio of total cholesterol to HDL cholesterol was 4.75. Comparison with a rural agricultural population showed that unadjusted blood pressure profiles differed significantly, but not when the profiles were adjusted for variation in concomitants (e.g., age, weight, fatness, etc.). It is hypothesized that the "intrinsic" blood pressure profiles of both populations are similar and that genes influencing physical variables (e.g., fatness) do not directly influence blood pressure. © 1994 Wiley-Liss, Inc.

HP, GC and PI polymorphisms in sixteen central Indian tribal populations.

HP, GC and PI polymorphisms have been typed on 16 Central Indian tribal populations with a total of 1658 individuals. The distribution of allele frequencies shows a statistically highly significant heterogeneity, which may be caused by several microevolutionary factors, such as genetic drift, social and geographic isolation. Some new variants were observed in both the GC system (GC 2Cmah) and in the PI system (PI Yori). The PI variants are more frequent and are found in most of the 16 populations under study whereas the GC variants are rather infrequent and restricted to only three populations.

Study of enzyme polymorphism and haemoglobin patterns amongst sixteen tribal populations of central India (Orissa, Madhya Pradesh, and Maharashtra).

A survey was conducted to study the genetic differentiation among 16 tribal groups of Orissa, Madhya Pradesh, and Maharashtra belonging to different ethnic and linguistic affiliations. Sixteen hundred and fifteen blood samples from both sexes were tested for 5 red cell enzyme systems: ACP, ESD, PGD, GLO, LDH, and Hb pattern. Three hundred and nineteen male individuals were tested for G-6-PD enzyme deficiency. The distribution of the enzyme markers and Hb show a range of variation which are more or less within the Indian range. Cases of homozygous HbSS were detected in all the tribes except 3 tribes in Orissa. Two cases of LDH Cal-1 homozygote were found in two Dravidian language speaking Orissa tribes. The chi 2-values for testing the homogeneity of gene frequencies indicate a non-significant heterogeneity for all alleles in the individual system. Within population diversity seems to be larger than between population diversity. The degree of over all genetic differentiation as measured by GST value is 0.0154 +/- 0.0071.

Predicting survival in burned patients.

Data pertaining to 562 consecutive admissions for burn treatment were analysed to identify factors related to survival. Besides socioeconomic, demographic and burn-related variables, three indices to measure burn severity, were proposed and evaluated with the help of multiple regression and discriminant analyses. The results of multiple regression analysis showed that one of the proposed indices, total burned surface (TBS), based on presence or absence of burn injury on 11 different body sites, turned out to be the best single predictor of survival. TBS alone accounted for 64.5 per cent of the total variance in survival variable. Combined use of TBS with type and severity of burn, age, sex, etc. did not appreciably raise the value of R2. The results of the discriminant analysis yielded a cut-off point of 20 TBS score which provided maximum separation between survivors and fatalities. Using this cut-off point (20 per cent) the TBS index provided the correct prediction of the eventual survival status in about 93 per cent of 562 patients. This cut-off point score of 20 was cross-validated on an independent sample of 924 cases. The prediction in 79 per cent of patients could be made correctly.

Investigations on the variability of blood group polymorphisms among sixteen tribal populations from Orissa, Madhya Pradesh and Maharashtra, India.

Sixteen tribal populations from Orissa, Madhya Pradesh and Maharashtra have been typed for the polymorphic blood group systems A1A2B0, MNSs, Rhesus, Kell, Duffy and Diego. The heterogeneity in the distribution of haplotype and allele frequencies, respectively, is partly considerable. It is supposed that this is due to the operation of several microevolutionary factors, such as genetic drift, social and geographic isolation and gene flow. This is discussed in detail.

Genetic study of five populations of Bihar, India.

Four-hundred fifty-nine people, including 106 Santals, 43 Bhuiyas, 107 Sakaldipi Brahmins, 108 Chamars, and 95 Ansari Muslims, of the Giridhi district of Bihar have been tested for transferrin, group-specific component, phosphoglucomutase subtypes, and glyoxalase-I, 6-phosphogluconate dehydrogenase, and adenylate kinase types. Genetic distance estimates by both dendrogram and principal component methods for these 5 populations and the Oraons on the basis of 19 alleles at 6 polymorphic loci indicate 2 major clusters: Brahmins and Muslims, the latter of which is composed of two subclusters (Santals and Bhuiyas, and Oraons and Chamars). The Santal and Bhuiya tribes both speak Mundari, whereas the Oraons speak a Dravidian language. The Chamars, although low-caste Hindus, seem to have a non-Europoid origin, as do the Oraons.

High prevalence of haemoglobin E in three populations of the Malda district, West Bengal, India.

High frequencies of haemoglobin (Hb) E were reported earlier from Assam in northeast India. In the present study one of the three populations of the Malda district of West Bengal, called the Deshi, was found to show one of the highest incidences of the Hb E gene (0.61) recorded so far. A founder effect and/or local inbreeding may possibly explain this observation.

The distribution of some serum protein and red cell enzyme polymorphisms in the Koch ethnic group of West Bengal, India.

Three populations (Poliya, Deshi, and Tiyor) of the Koch ethnic group have been studied for the distribution of three serum protein and four red cell enzyme polymorphisms. There was no significant difference in the allelic frequencies of these systems in the three populations of the Koch ethnic group. The overall gene frequencies were as follows: Hp1, 0.21; Gc1F, 0.34; Gc1S, 0.36; Gc2, 0.30; TfC1, 0.66; TfC2, 0.26; TfC3, 0.001; TfD, 0.06; GLO1, 0.21; PGI2, 0.04; AK2, 0.01; PGM1+, 0.80; PGM1-, 0.06; PGM2+, 0.11 and PGM2-, 0.02. The phenotypic distribution at all the loci was at Hardy-Weinberg equilibrium.

Genetic epidemiological study of blood pressure in a sedentary rural agricultural population of West Bengal, India.

To study the genetic epidemiology of blood pressure (BP), data on 78 families were collected from a sedentary agricultural population of eastern India. The general levels of both systolic (SBP) and diastolic (DBP) blood pressures are found to be low (mean SBP = 106.41 mm Hg; mean DBP = 63.94 mm Hg). Trends of blood pressures with age are similar to those reported earlier (e.g., in the Framingham study). Environmental variables--e.g., occupation and tobacco use--do not have any direct significant effect on blood pressure variability in this population. Path analysis of family data shows a highly significant familial aggregation and yields a genetic heritability (maximum) estimate of 0.3 for both SBP and DBP. Sib-sib and mother-child correlation estimates are, respectively, 0.3 and 0.25. Father-child correlation estimates are 0.13 for SBP and near zero for DBP. A pseudopolygenic model yields the best fit to the data on SBP, while for DBP a proper resolution of various models considered could not be obtained.

Genetic differentiation among four groups of fishermen of the eastern coast, India.

The four endogamous groups of fishermen living around the city of Puri, located on the eastern coast of India, were studied for blood groups, red cell enzymes and serum proteins (11 loci). Only 1.3% of the total diversity among the groups studied is due to differences between them (GST = 0.013). The genetic distances between populations were estimated using Edwards and Cavalli-Sforza's method. The pattern of genetic distance reflects the geographical distribution of these groups. In general, these observations support the patterns of variation based on anthropometric and dermatoglyphic variables.

Familial aggregation of blood pressure and anthropometric variables in patrilocal households.

Fifty-three households in a small Indian fishing community were surveyed for blood pressure, pulse rate, and anthropometric measurements (height, weight, and three skinfolds). In addition to nuclear family relationships, correlations for extended family members and in-laws living within a common household were estimated by maximum likelihood. Based on likelihood ratio tests, the hypothesis that correlations among genetically unrelated pairs from the same household are zero is rejected for systolic blood pressure. Among genetically related individuals, the degree of relationship does not affect the magnitude of the blood pressure correlations. For the anthropometric measurements, family resemblance is significant only for first-degree relatives, except that the correlation for uncle-child pairs is significant for subscapular skinfold, and brother-in-law-sister-in-law pairs resemble each other for height and weight. The results suggest that common household environment is a significant determinant of blood pressure but not fatness in this population.

Genetic heterogeneity and population structure in eastern India: red cell enzyme variability in ten Assamese populations.

This paper is a part of the genetic study of the people of Assam (eastern India), initiated by the Anthropometry and Human Genetics Unit, Indian Statistical Institute, Calcutta, India, and the Dept. of Human Biology/Physical Anthropology, University of Bremen, W. Germany. The results of 1. allele distribution of five red cell enzyme polymorphisms in ten Assamese populations, 2. heterogeneity of allele frequencies and extent of gene differentiation among these populations, and 3. standard genetic distances are presented here. A total of 1024 blood samples was screened for aP, E D, AK, ADA and LDH enzyme systems for Brahmins, Kalitas, Kaibartas, Rajbanshis, Muslims, Ahoms, Chutiyas, Kacharis, Karbis (Mikirs) and Sonowals, of which the latter three are tribes. The gene diversity (FST) is smallest (0.0035) for pa and highest (0.1604) for HbE. The total FST value (0.0399 +/- 0.0141) appears to be statistically significant. From distance analysis two major clusters with sub-clusters in each are visible, which are in conformity with the ethnohistory of these populations.