The findings may help to explain why some children are more attracted to sweet-tasting foods, as well as why taste and food preferences appear to change with age.
"The sense of taste is an important determinant of what children eat. We know that young children eat what they like. We also know that many children do not like bitter taste, thereby interfering with vegetable consumption and potentially limiting intake of important nutrients," comments lead author Julie Mennella, PhD, a developmental psychobiologist. "The recent Nobel Prize award demonstrates the importance of the identification of genes coding for taste and olfactory receptors. We took advantage of this new knowledge to look at how variation in taste genes might relate to the taste likes and dislikes of children and parents."
In the study, to be published in the February 2005 issue of Pediatrics, researchers compared taste sensitivity and food-related behaviors across three genotypes of the TAS2R38 gene, which encodes a taste receptor responsive to bitter taste.
Using cheek swabs to obtain genetic samples, researchers classified 143 children and their mothers into three groups based on their TAS2R38 genotype: Type AA had two bitter-insensitive sites (alleles), type PP had two bitter-sensitive alleles, and type AP had one of each.
To provide a behavioral measure of sensitivity to bitter taste, children who were between 5 and 10 years of age - and mothers categorized three concentrations of a bitter-tasting compound (propylthiouracil; PROP) as tasting either "like water" or "bitte
Contact: Julie Mennella, PhD
Monell Chemical Senses Center