CREBRF and dietary intake: The relationship between dietary intake and the CREBRF rs373863828 genetic variant in healthy men of Polynesian ancestry

Abstract

Background: On average, Polynesian peoples (Pacific peoples and Aotearoa New Zealand Māori) living in New Zealand have higher BMI (body mass index) than other ethnic groups. One factor contributing to this effect is the unique genetic variation within people of Polynesian ancestry. The minor A allele of rs373863828 (CREBRF p.Arg457Gln) is associated with increased BMI, but reduced risk of type 2 diabetes mellitus (T2DM) in Polynesian populations. It is not known why the minor A allele is associated with greater BMI; however, differences in dietary intake may contribute to this effect. Aim: This study investigates the relationship between the rs373863828 genotype and dietary intake, dietary patterns, and overall diet quality in overweight and obese men of Polynesian ancestry without chronic disease. Methods: The study design of the overarching study was cross-sectional. A validated 154- item semi-quantitative food frequency questionnaire (FFQ) was used to collect dietary data from 168 men of Māori (33 with the A allele) and Pacific (67 with the A allele) ancestry. Dietary patterns were established through Principal component analysis. The association between dietary patterns and the risk of obesity was examined and adjusted for ancestry and rs373863828 genotype by logistic regression. Diet quality scores were produced using reported intake from the FFQ against the validated Healthy Dietary Habits Index (HDHI) for New Zealand adults. Mixed linear models with covariates age, ancestry, and BMI were used to analyze the association between rs373863828 genotypes, dietary intake, dietary patterns, and diet quality scores. Results: The A allele of rs373863828 did not associate with daily energy or macronutrient intake. However, the A allele is associated with a greater frequency of intake per day of cereal foods (P<0.05). Consistent with this finding, the A allele is associated with higher daily fiber intake. Three distinctive dietary patterns across all participants were identified from our analyses – Grains and animal, Dairy and plant, and Sugar, snacks, and drinks. The identified dietary patterns were not associated with an increased risk of obesity. There was no significant difference found in the diet quality scores between rs373863828 genotypes. Conclusions: This study provides evidence that the CREBRF rs373863828 A-allele does not associate with total energy intake. Similarly, dietary patterns of rs373863828 genotypes does not associate with increased risk of obesity. The rs373863828 A-allele is associated with higher intake of fibre and cereal foods. An alternative hypothesis, consistent with this data, is that those with the A allele consume foods that have a protective role against T2DM. Further research across a significantly larger cohort representative of the general Polynesian population is required to confirm these findings.