Smell acuity for acetone and its relationship to taste ability to phenylthiocarbamide in a Nigerian population.

Acetone smell sensitivity and phenylthiocarbamide taste sensitivity thresholds have been measured simultaneously for 970 Nigerians (542 males and 428 females) using modified sorting techniques. The distribution was bimodal in both cases and the frequency of subjects with high smell acuity for acetone was 9.6% while that of non-tasters was 12.60% with a gene frequency, as computed by maximum likelihood methods, of 0.355 +/- 0.015. Females showed a higher frequency for smell sensitivity to acetone but a slightly lower frequency of non-tasters compared to males. Acetone smell sensitivity and PTC with high smell acuity for acetone were tasters while 30.28% of subjects least sensitive taste ability decreased with age in the overall population. All the subjects least sensitive to acetone were non-tasters, a significantly higher proportion than in the overall population. The correlation between acetone smell acuity and phenylthiocarbamide taste ability demonstrates a strong allelic association. All the 94 individuals with high smell acuity for Acetone were tasters for phenylthiocarbamide.