Role of phenylthiocarbamide as a genetic marker in predicting the predisposition of disease traits in humans

The main objective of this study is to find out the genetic variation and predisposition of overweight/obese, smoking/alcoholism and thyroid disease traits among tasters and non-tasters in Mysore population, South India. Bitter-taste perception for phenylthiocarbamide (PTC) is a classically variable trait both within and between human populations. Many studies have reported that in world population, approximately 30% of them are PTC non-tasters and 70% are tasters. This investigation was conducted during the year 2009-2010 involving a total 1352 study subjects and divided into three different groups, considering the age ranging from 13 to 50 years. Phenylthiocarbamide taste sensitivity was measured by administering a freshly prepared 0.025% of phenylthiocarbamide solution using the Harris and Kalmus method with a slight modification and the results were recorded. In the first group of 100 obese/overweight children, 28% are taster and 72% are non-taster and among 100 control group 67% are tasters and 43% are non-tasters. In second group, out of 1152 individuals 710 (61.63%) are tasters and 442 (38.37%) are non-tasters including both males and females. In the third group, out of each 100 thyroid patients and the control group, tasters are significantly more frequent (61.41%) than the non-tasters (38.58%) in the control group, but a higher proportion of non-tasters are recorded among individuals with thyroid problems (68%) compared to tasters (32%). There is a significant higher incidence of PTC tasters than non-tasters among general population in this study. As phenotypic variation in PTC sensitivity is genetic in origin, this may represent a surrogate risk factor for the development of multifactorial disease and disorders.