RESUMO
BACKGROUND: Methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism has been suggested to be positively associated with several disorders. Distribution of the mutant T-allele varies in ethnic and geographical populations of the world. AIM: The aim of the present study was to investigate the distribution of methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism in a transhumant (Gaddi) tribal population of Himachal Pradesh dwelling at high and middle altitude and exposed to strong ultraviolet radiation. METHOD AND RESULTS: A total of 486 samples (141 males and 345 females) were randomly enrolled from the individuals aged 25-75 years who were unrelated up to first cousin. Among Gaddis, genotype frequencies of CC, CT and TT were 67.90%, 27.78% and 4.32%, respectively. Among males and females distribution of genotype frequencies also followed a similar trend. The studied population was in Hardy-Weinberg equilibrium (χ(2 )= 2.213, df = 1, p = 0.136). Frequency of mutant T-allele in the Gaddi population was found to be 0.183, which might be due to European ancestry, endogamous nature and selection.
