<b><i>TRPV1</i></b> Gene Polymorphisms Are Associated with Type 2 Diabetes by Their Interaction with Fat Consumption in the Korean Genome Epidemiology Study

Abstract

Background: Different transient receptor potential vanilloid 1 (TRPV1) variants may be differently activated by noxious stimuli. Aim: We investigated how TRPV1 variants modulated the prevalence of type 2 diabetes and specific gene-nutrient interactions. Methods: Among 8,842 adults aged 40-69 years in the Korean Genome Epidemiology Study, the associations between TRPV1 genotypes and the prevalence of type 2 diabetes as well as their gene-nutrient interactions were investigated after adjusting for the covariates of age, gender, residence area, body mass index, daily energy intake, and total activity. Results: The TRPV1 rs161364 and rs8065080 minor alleles lowered HOMA-IR and the risk of type 2 diabetes after adjusting for covariates. There were gene-nutrient interactions between TRPV1 variants rs161364 and rs8065080 and preference for oily taste, intake of oily foods, and fat intake after adjusting for covariates. Among subjects with the minor alleles of TRPV1 rs161364 and rs8065080, the group with a high preference for oily foods had a lower odds ratio for type 2 diabetes. Consistent with the preference for taste, among subjects with the minor alleles, the group with high fat intake from oily foods also exhibited a lower risk of type 2 diabetes than subjects with the major alleles. Conclusions: People with the minor alleles of the TRPV1 single nucleotide polymorphisms rs161364 and rs8065080 have a lower risk of diabetes with a high-fat diet, but people with the major alleles are at a higher risk of type 2 diabetes when consuming high-fat diets. The majority of people should be careful about a high fat intake.

High Genetic Risk Scores of <b><i>ASIC2, MACROD2, CHRM3</i></b>, and <b><i>C2orf83</i></b> Genetic Variants Associated with Polycystic Ovary Syndrome Impair Insulin Sensitivity and Interact with Energy Intake in Korean Women

“…The area under the curve (AUC) of glucose and insulin was calculated by the trapezoidal rule. Insulin resistance was assessed using the homeostasis model assessment estimate (HOMA) of insulin resistance (HOMA-IR = fasting insulin levels [µIU/mL] × fasting glucose levels [mM]/22.5) [22]. Insulin secretion capacity was represented by HOMA-B.…”

“…Insulin secretion capacity was represented by HOMA-B. HOMA-B was calculated as (20 × fasting insulin levels)/(fasting glucose levels -3.5) [22]. The subjects were categorized into 2 groups by the HOMA-IR with the cut-off level of 2.0 (the 75th percentile) and the HOMA-B with the cut-off point of 120 (the 25th percentile).…”

“…The accuracy and reproducibility of the SQFFQ for measuring the average consumption of food items during the previous year by Koreans have been validated to be acceptable [22]. The SQFFQ includes 103 food items, and food frequencies are divided into the following 9 categories: never or seldom, once per month, 2-3 times per month, 1-2 times per week, 3-4 times per week, 5-6 times per week, once per day, twice per day, and 3 times or more daily.…”

“…The genotyping and quality-control processes were described in detail previously [21,22]. DNA samples from the participants were isolated from their peripheral blood, and genotyping was conducted using the Affymetrix Genome-Wide Human SNP array 5.0 (Affymetrix, Santa Clara, CA, USA).…”

Gene-Diet Interactions in Type 2 Diabetes: The Chicken and Egg Debate

“…A Korean Genome Epidemiology Study demonstrated that individuals with the minor alleles of the TRPV1 single nucleotide polymorphisms (SNPs) rs161364 T>C and rs8065080 T>C were negatively associated with the prevalence of T2DM. They also determined that carriers of the minor allele of both SNPs have a lower risk of diabetes with a high-fat diet but individuals with the major alleles are at a higher risk of T2DM when consuming high-fat diets [215]. …”