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Biomedical subjects

S M Chahal

Publications and source records attributed to S M Chahal.

At least 19 recordsLinked to original sources

Variability of genetic markers in Himachal Pradesh, India: variation among the subpopulations.

The genetic composition of one tribal and two nontribal populations of the Chamba District, Himachal Pradesh, India, was studied by phenotype analyses of 25 genetic markers (9 blood groups, 13 red cell enzymes, and 3 serum proteins). Furthermore, the genetic structure of 11 populations from 3 districts, Chamba, Kangra, and Kinnaur of Himachal Pradesh, was also analyzed using data from 20 loci (57 alleles). Nine genetic systems (ABO, Rh, FY, P, PGM, ACP, AK, PGD, and HP) showed highly significant heterogeneity in the five populations of Kinnaur District, whereas among the six populations from Chamba and Kangra districts the genetic variation was low. The FIS value at each locus for the five populations of Kinnaur District and the six populations from Chambra and Kangra districts was consistently higher than the FST estimates, suggesting that the population structure of both regions is influenced by local random inbreeding. Although the role of selection in local genetic differentiation cannot be ruled out, the present analyses indicate that local differentiation is mainly affected by geographic proximity, random inbreeding, and admixture.

Ethnicity↗

Polymorphic protein expression (profile) in numigall.

Ten protein and enzyme polymorphic systems, viz. haemoglobin, albumin, transferrin, adenosine deaminase, adenylate kinase phosphoglucomutase, esterase-D, glyoxalase, alkaline phosphatase and amylase were studied in numigall (guinea fowl x chicken hybrids) to assess structural gene expression and regulatory gene divergence between the parental species. The investigation revealed presence of both the maternal and paternal electrophoretic components in case of adenosine deaminase, alkaline phosphatase, amylase, albumin and transferrin although no clear differences could be identified for haemoglobin and glyoxalase. Esterase-D and adenylate kinase phenotypes showed a dominance of the chicken type.

Animals↗

Genetic epidemiology of non-insulin-dependent diabetes mellitus in north India: preliminary analyses of some genetic markers in Punjabis.

Studies on monozygotic (MZ) twins and admixed populations show that the predisposition to non-insulin-dependent diabetes mellitus has a large genetic component. We have examined the distribution of some genetic polymorphisms (ABO, GLO, ESD, AK, ACPA, and GPI) in control and diabetic Punjabis from north India. The distribution of various genetic markers indicate that the differences between the control and diabetic samples are statistically not significant. Moreover, a contingency chi-square analysis over all loci suggests nonsignificant genetic differentiation (p = 0.50) between the Punjabi samples.

Adult↗

Serogenetic variation in four caste populations of Haryana, India.

The phenotypes and gene frequencies of 3 blood groups, 7 red-cell enzymes and a serum protein were studied in 4 caste population groups of Haryana, North India. The results indicate that the distribution of these blood markers is rather homogeneous in the 4 groups and generally resembles that observed in various populations from neighbouring North Indian states.

ABO Blood-Group System↗

Erythrocyte enzyme polymorphisms in the Kamboh caste of Patiala, Punjab.

Data are presented on six erythrocyte enzyme polymorphisms (ADA, GLO I, EsD, AK, AP, GPI) in the Kamboh, a scheduled caste inhabiting the Patiala district of the Indian state of Punjab. With their high ADA2 (18.5%), Pa (42.5%) and GPI3 (5.3%) and a rather low GLO1 (18.8%) frequencies, the Kamboh differ from all other populations of Punjab.

Data Interpretation, Statistical↗

Electrophoretic variants of red cell phosphoglucose isomerase in some caste populations of Punjab.

Hemolysates from a total of 640 blood samples from seven endogamous caste groups of the Patiala and Faridkot districts of Punjab, North-West India, were subjected to horizontal starch gel electrophoresis to study the phosphoglucose isomerase (PGI) types. In addition to the usual pattern PGI 1, the only rare phenotype encountered in the present material was PGI 3-1, present in four out of the seven groups investigated. Examination of the available data from Punjab suggests that apparently rare PGI types other than PGI 3-1 are lacking in populations studied.

Electrophoresis, Starch Gel↗

Genetic studies of Pangwalas, Transhumant and Settled Gaddis. 4. Colour blindness, mid-phalangeal hair, ear lobe attachment and behavioural traits.

Frequency distributions of colour blindness, midphalangeal hair, ear lobe attachment, hand clasping, arm folding, leg folding and handedness are reported for different population groups from Himachal Pradesh, North India, namely Pangwalas, Transhumant Gaddis (Brahmans, Rajputs and Scheduled Castes) and Settled Gaddis (Brahmans, Rajputs and Schedules Castes). An attempt has been made to compare the results of the present study within and between these groups as well as with the results of other reports from different population groups of India and Asia.

Color Vision Defects↗

Population genetics of glyoxalase I (GLO) polymorphism in India.

Phenotype and gene frequency data are presented on the glyoxalase I (GLO) polymorphism in seven endogamous caste groups: Jat Sikh, Ramdasia Sikh, Ramgarhia Sikh, Khatri, Brahmin and Bania of Patiala district, and Jat Sikh of Faridkot district of Punjab, North-West India. Apparently, there is considerable heterogeneity in the frequency distribution of the GLO1 gene that varies from 0.168 in Bania to 0.287 in Brahmin. However, these differences are not statistically significant, and the overall GLO1 frequency in Punjab is well within the North Indian range.

Gene Frequency↗

Genetic variation of esterase D (EsD) polymorphism in Indian populations.

Data are presented on the phenotypes and gene frequencies of esterase D (EsD) polymorphism in various endogamous caste groups of Patiala and Faridkot districts of Punjab, north-west India. The frequency of the EsD2 allele in these groups varies from a minimum of 0.157 in Khatris to a maximum of 0.253 in Ramdasia Sikhs, a range quite typical of the north Indian populations. Examination of the available data on esterase D system in indigenous populations demonstrates the existence of a north-south cline in the distribution of the EsD2 allele in India.

Carboxylesterase↗

Genetic polymorphism of erythrocyte acid phosphatase in Indian populations.

The polymorphism of erythrocyte acid phosphatase has been investigated in seven endogamous caste groups of Patiala and Faridkot districts of Punjab in north-west India. The frequency of the Pa allele in these groups varies from 26.8 to 38.3%, but there is no evidence for any significant heterogeneity in the total sample. The Pc allele is present in some of the groups, though in non-polymorphic proportions. Furthermore, the distribution of this polymorphism in Indian populations has been examined using gene frequency data available in the literature. The present study shows that while no clinal component is discernible in the distribution of this red cell enzyme in India, the populations of north India stand out with comparatively high Pa and Pc frequencies, and in almost all regions the incidence of these two alleles is higher in the non-tribals as compared to the tribals. The possible causes of this heterogeneity are discussed.

Acid Phosphatase↗

Population genetics of the group specific component (Gc) and phosphoglucomutase (PGM1) studied by isoelectric focusing.

For the determination of the group-specific component (Gc) and phosphoglucomutase (PGM1) phenotypes, isoelectric focusing was performed on two samples, one of Jat Sikh of northwest India, the other of northeast English. The subtype frequencies of these two systems do not differentiate the two populations sampled. Synthesis of the existing data shows distinct PGM1 and Gc subtype frequencies in various ethnic and racial groups. The anthropological implication of these subtype frequencies is discussed.

Alleles↗