ABO and Rh D polymorphism among Tibetans in India
Vikal Tripathy1, Kanhu Charan Satapathy, Ranjan Gupta
1Biological Anthropology Unit, Indian Statistical Institute, 203 Barrackpore Truck Road, 700108 Kolkata.
Human Biology
|October 14, 2006
Summary
This study analyzed ABO and Rh D blood group allele frequencies in 923 exiled Tibetans in India. Findings indicate genetic stability across locations and an East Asian affinity, with ABO system in Hardy-Weinberg equilibrium.
Area of Science:
- Population genetics
- Human genetics
- Anthropology
Background:
- ABO and Rh D blood group systems are crucial for human genetic diversity studies.
- Understanding genetic polymorphisms in isolated populations like Tibetans provides insights into migration and adaptation.
- Previous studies on Tibetan populations have shown varying genetic profiles.
Purpose of the Study:
- To determine the allele frequencies of the ABO and Rh D blood group systems in exiled Tibetan populations in India.
- To investigate potential genetic variations across different geographical locations (high and low altitudes).
- To assess the genetic equilibrium and population affinities of this Tibetan cohort.
Main Methods:
- Blood samples were collected from 923 exiled Tibetans residing in four distinct locations in India.
- ABO and Rh D blood group typing was performed using standard serological methods.
- Allele frequencies were calculated and statistically analyzed to compare groups and test for Hardy-Weinberg equilibrium.
Main Results:
- The allele frequencies for the ABO system were p=0.1295, q=0.2544, and r=0.6152.
- The allele frequencies for the Rh D system were D=0.9428 and d=0.0572.
- No significant differences in allele frequencies were observed among the four study locations.
- The ABO blood group system was found to be in Hardy-Weinberg equilibrium.
Conclusions:
- Exiled Tibetan populations in India exhibit stable ABO and Rh D allele frequencies irrespective of altitude.
- The observed allele frequencies suggest a genetic affinity with East Asian populations.
- The Hardy-Weinberg equilibrium for the ABO system indicates a lack of significant evolutionary pressure in this cohort.
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