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B. Karmakar

Bio: B. Karmakar is an academic researcher from Indian Statistical Institute. The author has contributed to research in topics: Population & Dermatoglyphics. The author has an hindex of 10, co-authored 34 publications receiving 274 citations.

Papers
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TL;DR: The main goal of the present communication is to determine the mode of inheritance of dermatoglyphic diversity traits through complex segregation analyses (genetic model fittings) of a large ethnically homogeneous sample of 500 Indian pedigrees.
Abstract: The main goal of the present communication is to determine the mode of inheritance of dermatoglyphic diversity traits through complex segregation analyses (genetic model fittings). The data consists of a large ethnically homogeneous sample of 500 Indian pedigrees (2435 individuals) of two generations. Principal component analysis, familial correlations and segregation analysis (package MAN-5) were used. A little genetic effect obtained from familial correlations but no evidence of major gene contribution found to be involved. By segregation analysis of the traits- PC 1_ Div, Div 9 and Div 11, both Mendelian and Environmental models were rejected (<<0.001) with the General model, i.e. despite the presence of significant inheritance (rejection of Environmental model), the nature of inheritance is more complex, than Mendelian model.

3 citations

Journal ArticleDOI
TL;DR: Heterogeneity for most of the anthropometric and some dermatoglyphic traits supports their different origins and heterogeneity in anthropometric asymmetry corroborates with their different occupations.
Abstract: The present paper focuses on the interethnic comparison among three endogamous groups (a higher caste, a tribe and a religious group) with different ethnohistorical background. A total of 700 individuals were studied from their anthropometric and dermatoglyphic traits along with their asymmetries. Statistical comparisons were carried out through the use of student’s ‘t’ test and Sanghvi’s T2 statistics. Heterogeneity for most of the anthropometric and some dermatoglyphic traits supports their different origins. Though dermatoglyphic asymmetry doesn’t reveal significant discrimination, heterogeneity in anthropometric asymmetry corroborates with their different occupations. The anthropometric distances show greater values than the dermatoglyphic distances. This difference is probably due to the fact that anthropometry is not independent of environment and not a stable character like dermatoglyphic traits.

3 citations

Journal Article
TL;DR: Although a little genetic effect was observed due to familial correlations on asymmetry traits, no evidence was found of major gene contribution to be involved, but this does not contradict the notion postulated by several earlier authors that asymmetry provides a measure of developmental instability in human.
Abstract: The major aim of this study is to determine the mode of inheritance of asymmetry of quantitative dermatoglyphic traits based on principal factors through the application of complex segregation (genetic model fitting) analyses on a large ethnically homogeneous sample of 500 Indian pedigrees (2435 individuals) of two generations. By segregation analysis of the traits- PC1_FA both Mendelian and Environmental models were rejected (< 0.001) with the General model, i.e. that despite presence of significant inheritance (rejection of Environmental model), the nature of inheritance is more complex, than Mendelian one. Although a little genetic effect was observed due to familial correlations on asymmetry traits, no evidence was found of major gene contribution to be involved, but this does not contradict the notion postulated by several earlier authors that asymmetry (fluctuating) provides a measure of developmental instability in human.

3 citations

Journal ArticleDOI
TL;DR: Evidence of strong genetic component in finger pattern types is provided and seems more informative compared to the earlier traditional method of correlation analysis.
Abstract: Digital patterns of a sample on twins were analyzed to estimate the resemblance between monozygotic (MZ) and dizygotic (DZ) twins and to evaluate the mode of inheritance by the use of maximum likelihood based variance decomposition analysis. MZ twin resemblance of finger pattern types appears to be more pronounced than in DZ twins, which suggests the presence of genetic factors in the forming of fingertip patterns. The most parsimonious model shows twin resemblance in count of all three basic finger patterns on 10 fingers. It has significant dominant genetic variance component across all fingers. In the general model, the dominant genetic variance component proportion is similar for all fingertips (about 60%) and the sibling environmental variance is significantly nonzero, but the proportion between additive and dominant variance components was different. Application of genetic model fitting technique of segregation analyses clearly shows mode of inheritance. A dominant genetic variance component or a specific genetic system modifies the phenotypic expression of the fingertip patterns. The present study provided evidence of strong genetic component in finger pattern types and seems more informative compared to the earlier traditional method of correlation analysis.

2 citations

Journal ArticleDOI
TL;DR: In this article, a sample of 3000 males belonging 20 endogamous castes from Maharashtra were analysed to determine specifically the distribution of
Abstract: In a sample of 3000 males belonging 20 endogamous castes from Maharashtra were analysed to determine specifically the distribution of

2 citations


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TL;DR: For the next few weeks the course is going to be exploring a field that’s actually older than classical population genetics, although the approach it’ll be taking to it involves the use of population genetic machinery.
Abstract: So far in this course we have dealt entirely with the evolution of characters that are controlled by simple Mendelian inheritance at a single locus. There are notes on the course website about gametic disequilibrium and how allele frequencies change at two loci simultaneously, but we didn’t discuss them. In every example we’ve considered we’ve imagined that we could understand something about evolution by examining the evolution of a single gene. That’s the domain of classical population genetics. For the next few weeks we’re going to be exploring a field that’s actually older than classical population genetics, although the approach we’ll be taking to it involves the use of population genetic machinery. If you know a little about the history of evolutionary biology, you may know that after the rediscovery of Mendel’s work in 1900 there was a heated debate between the “biometricians” (e.g., Galton and Pearson) and the “Mendelians” (e.g., de Vries, Correns, Bateson, and Morgan). Biometricians asserted that the really important variation in evolution didn’t follow Mendelian rules. Height, weight, skin color, and similar traits seemed to

9,847 citations

Journal ArticleDOI
01 Nov 2016-Thyroid
TL;DR: A systematic review supports a widespread and persistent increase in TC incidence and evidence for over-detection of PTC as the predominant influence includes increased numbers of smaller size tumors and improved or unchanged survival.
Abstract: Background: A large proportion of global increase in thyroid cancer (TC) incidence has been attributed to increased detection of papillary thyroid cancer (PTC). Nonetheless, some reports support a real increase in incidence. This study aimed to perform a systematic review to evaluate the changing trends in TC incidence and summarize potential risk factors predisposing to this trend. Methods: Literature published in the English language between 1980 and August 2014 was searched via PubMed (MEDLINE) and OvidSP (EMBASE). Original studies on changes in TC incidence in defined geographic areas that described clear methods of case selection and population estimates were included. Data on incidence rates and risk factors were collected. Results: Of 4719 manuscripts, 60 studies were included, of which 31 were from Europe, 13 from North America, and the rest from Asia (n = 9), Oceania (n = 4), and South America (n = 3). Fifty-three articles reported a significant increase in incidence (highest was a 10-fold increa...

247 citations

Journal ArticleDOI

241 citations

Journal ArticleDOI
TL;DR: This foetus into man physical growth from conception to maturity will help people to enjoy a good book with a cup of coffee in the afternoon instead of facing with some malicious virus inside their desktop computer.
Abstract: Thank you for downloading foetus into man physical growth from conception to maturity. As you may know, people have look numerous times for their chosen novels like this foetus into man physical growth from conception to maturity, but end up in infectious downloads. Rather than enjoying a good book with a cup of coffee in the afternoon, instead they are facing with some malicious virus inside their desktop computer.

234 citations