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Objective: Premenstrual syndrome (PMS) is still a poorly understood and accepted condition. We evaluate the phenotypic variations at TAS2R38 gene locus in relation to PMS severity and adiposity measures among adult women. This is the first ever report describing association of PTC taste genetic locus with the PMS susceptibility., Methods: The study was based on a cross-sectional sample of 105 adult rural women from the Kullu district, Himachal Pradesh. Retrospective approach was used to assess PMS. PTC tasting ability was assessed after Harris & Kalmus (1949). Each subject was measured for height, weight and body fat measures., Results: 19.05% of the females were PTC non-tasters and 80.95% were tasters. Prevalence of PMS was 45.71%. Prevalence of severe type of PMS was very low, varying from 0-6%. Severity was highest in PMS-A type characterized by anxiety/irritability, tension, clumsiness, mood swings, nervousness, and insomnia. Females who tasted PTC bitter at lower concentrations had lowest PMS prevalence, while those who tasted PTC at higher concentration had highest PMS prevalence. Stature and body weight decreased with increase in PTC taste sensitivity. However, one-way ANOVA revealed that all the F-ratios were insignificant between the three discrete categories of low, medium and high PTC thresholds., Conclusion: Our results are compatible with the hypothesis that the bitter receptor gene TAS2R38 could not serve as a significant predictor of anthropometric measurements though some indirect pathways may not be ruled out, but the gene is significantly correlated with PMS susceptibility and severity.

Background: Quantitative genetic studies revealed that not all of the phenotypic variance in PTC taste perception is heritable., Aim: To study quantitative variations in PTC tasting ability in twins and to estimate heritability of PTC taste perception on the taste of twin data on males and females sexes separately., Subjects and Methods: The data for PTC taste sensitivity following the classic method of Harris & Kalmus (1949) were collected on a sample of 141 twin pairs (66 MZ and 75 DZ) and 275 singletons (128 males and 147 females) from Chandigarh, India. Genetic analyses were performed following Christian (1979), Donner (1986) and Sham (1998)., Results: Frequency of non-tasters was similar in twins (33 %) and singletons (32 %), but significant sex differences were observed. No differences were found between zygosities for mean thresholds. Similarly, no evidence of variance heterogeneity and environmental covariance was seen between zygosities. Since no basic assumption of the twin method was found violated, within-pair estimates of genetic variance would be unbiased. These estimates were highly significant in both males and females. However, dominance and additive components of genetic variance were found to differ between sexes., Conclusion: PTC thresholds do not seem to be significantly affected by environmental factors as no variance inequality was observed between twin zygosities. Intensity of bitterness (scalar dimensions) of PTC is a separate trait having no commonality with the genetic basis of recognition threshold for PTC tasting ability. The receptors recognizing bitter taste are different from the receptors determining intensity of taste. The absolute difference between co-twins in PTC thresholds can be used as a simple tool in the twin zygosity diagnosis. The results show that none of the MZ co-twins had manifested difference of more than 3 in their PTC threshold.