Studies of Human Twins Reveal Genetic Variation That Affects Dietary Fat Perception

Abstract

<jats:title>Abstract</jats:title> <jats:p>To learn more about the mechanisms of human dietary fat perception, we asked 398 human twins to rate the fattiness and how much they liked 6 types of potato chips that differed in triglyceride content (2.5%, 5%, 10%, and 15% corn oil); reliability estimates were obtained from a subset (n = 50) who did the task twice. Some chips also had a saturated long-chain fatty acid (FA; hexadecanoic acid, 16:0) added (0.2%) to evaluate its effect on fattiness and liking. We computed the heritability of these measures and conducted a genome-wide association study (GWAS) to identify regions of the genome that co-segregate with fattiness and liking. Perceived fattiness of and liking for the potato chips were reliable (r = 0.31–0.62, P &amp;lt; 0.05) and heritable (up to h2 = 0.29, P &amp;lt; 0.001, for liking). Adding hexadecanoic acid to the potato chips significantly increased ratings of fattiness but decreased liking. Twins with the G allele of rs263429 near GATA3-AS1 or the G allele of rs8103990 within ZNF729 reported more liking for potato chips than did twins with the other allele (multivariate GWAS, P &amp;lt; 1 × 10–5), with results reaching genome-wide suggestive but not significance criteria. Person-to-person variation in the perception and liking of dietary fat was 1) negatively affected by the addition of a saturated FA and 2) related to inborn genetic variants. These data suggest that liking for dietary fat is not due solely to FA content and highlight new candidate genes and proteins within this sensory pathway.</jats:p>

Worldwide study of the taste of bitter medicines and their modifiers

“…Two genomic regions met the conventional threshold for statistical difference in the genome-wide association analysis within RIMS2 and THSD4 , two genes not known to be part of the human taste signaling system. In a twin study RIMS2 variants explained, in part, differences in liking for high-fat foods [57]; its protein product regulates synaptic membrane exocytosis. People with RIMS2 loss-of-function variants have visual and pancreatic defects [58], and this information, coupled with our knowledge that sweet taste cells lack conventional exocytotic synapses, suggest that RIMS2 may act to modify sucralose perception in cells other than taste receptors (e.g., in the brain or pancreas).…”

Taste of Fat and Obesity: Different Hypotheses and Our Point of View

“…What influences can the indoor environment, circulating factors (triglycerides, inflammatory factors, etc. ), hormones and the contents of the digestive tract or even the gut microbiota and genetic factors have on the reward system, the cognitive system and the taste/mouthfeel of fat in obesity [163,[222][223][224][225][226][227]? Do endocrine disruptors (bisphenol-A) alter the reward system in the prenatal and neonatal periods as observed in mice [228]?…”