Sensitivity to the taste of phenylthiocarbamide (PTC) and its chemical relative 6-n-propylthiouracil (PROP), both of which contain an N=C—S moiety, is suggested to be the phenotypical marker of PROP taster status, which is genetically inherited(Reference Hayes, Bartoshuk and Kidd1). Based on the response to such bitter-tasting compounds individuals can be classified as super-tasters (ST), medium-tasters (MT) or non-tasters (NT). The gene conferring PTC taster ability, TAS2R38, has three common single-nucleotide polymorphisms, responsible for the three taster categories. PROP sensitivity has been linked to increased sensitivity to other tastes, including sweet(Reference Drewnowski, Henderson and Barratt-Fornell2) and fat(Reference Tepper and Nurse3), which may in turn affect micronutrient intake(Reference Wooding, Kim and Bamshad4).
The present study aims to examine whether TAS2R38 genotype is related to micronutrient intake, in a group of Irish adults and children. The data was collected as part of a larger on-going project examining PROP taster status and its effect on fruit and vegetable intake. In the present study 408 children and 113 adults were recruited from the Dublin area. Micronutrient intakes were assessed through diet histories and analysed using WISP© (Tinuviel Software, Llanfechell, Anglesey, UK). TAS2R38 genotyping was assessed by extracting DNA from buccal-cell swabs using the QiAMP DNA minikit (Qiagen UK, Crawley, West Sussex, UK) and genotyped for variants in the TAS2R38 gene by K-Biosciences (Hoddesdon, Herts., UK). Statistical analysis was carried out using SPSS software (SPSS Inc., Chicago, IL, USA; ANOVA and post hoc t tests).
No significant differences were observed in adults for biotin, Ca, carotene, Cu, Cl, Fe, folate, I, K, P, Mg, Mn, Na, niacin, pantothenic acid, potential niacin, retinol, riboflavin, Se, thiamine, Zn or vitamins B12, B6, C, D, E and K. However, when split by gender folate and K intakes were found to be significantly different across taster groups in women (P=0.039 and P=0.048 respectively). No significant differences were observed in children for most of the micronutrients mentioned earlier, with the exceptions of riboflavin and vitamin B12 (P=0.041 and P=0.008 respectively). When split by gender vitamin B12 remained significant across taster groups in girls (P=0.020).
Values were significantly higher than those for children in the ST group: *P<0.05.
It is difficult to suggest why significant differences have been observed for riboflavin and vitamin B12 in children, and conclusions cannot be drawn until further analysis is carried out. Some of the exact reasons for this finding may become clearer when the food groups contributing to the differences in the mean daily intakes are analysed.
