Interaction of common variants of FTO gene and Dietary Inflammatory Index on obesity measures: Tehran Lipid and Glucose Study

TL;DR

This study explores how genetic variants in the FTO gene and diet quality interact to influence obesity measures like waist circumference.

Contribution

The study identifies a potential interaction between FTO gene variants and dietary inflammation on changes in waist circumference.

Findings

Higher adherence to a pro-inflammatory diet was linked to increased waist circumference in carriers of a specific FTO SNP risk allele.

A significant interaction was found between FTO rs1421085 and the Dietary Inflammatory Index regarding changes in waist circumference.

The relationship between diet and obesity measures varied depending on the FTO genotype.

Abstract

This study aimed to examine the interaction of Dietary Inflammatory Index (DII) and fat mass and obesity-associated gene (FTO) single-nucleotide polymorphisms (SNPs) on change in obesity measures.

A total of 4480 participants from the Tehran Lipid and Glucose Study were selected. DII was calculated using a Food Frequency Questionnaire. The FTO SNPs rs8050136, rs14211085 and rs1121980 were selected. Changes in obesity measures were calculated.

In individuals with risk allele of FTO SNP rs8050136, greater adherence to DII was associated with increased odds of higher waist circumference (WC) (OR, Q1–Q4: 1, 0.87, 0.88, 0.94; P trend=0.01), but deceased odds of waist to hip ratio (WHR) (OR, Q1–Q4: 1, 0.85, 0.76, 0.70; P trend=0.01). Moreover, higher score of DII was significantly related to elevated odds of having high Visceral Adiposity Index (VAI) in individuals with wild-type genotype of FTO SNPs. For changes in WC, a significant interaction was identified between FTO rs1421085 and DII; the second quartile of DII was associated with increased odds of having a high WC in carriers of wild variant (TT genotype) of rs1421085 (OR 1.43; 95% CI 1.04 to 1.97), but not in individuals with risk allele of this SNP (TC CC). Although there are significant relationships between SNPs or genetic risk score and change in WHR or VAI, but there is no significant interaction between FTO SNPs and DII regarding change in body mass index, WHR and VAI.

There may be an interactive effect between DII and the FTO rs1421085 genotypes on change in WC.