The role of FTO gene alleles on the diet and metabolic risk factors in the subjects with diabetes

Purpose: To evaluate the effect of differential food intake on metabolic risk markers in Type 2 diabetic individuals with diverse FTO gene alleles. Materials and Methods: The study was conducted at Baqai Institute of Diabetology and Endocrinology (BIDE) Karachi, Pakistan between March 2011 and May 2013. The present study is based on a previously published case-control study that indicates the association of different FTO gene with type 2 diabetes. The structured questionnaire was used to gather anthropometric, biochemical, and clinical data. Single nucleotide polymorphism (SNP) in FTO gene was analyzed using Amplification Refractory Mutation System-Polymerase Chain Reaction (ARMS-PCR). The nutritional data were collected using a 24-hour dietary recall questionnaire completed by a trained dietitian. The variations in energy and macronutrient intake of subjects having different FTO gene alleles were investigated and evaluated for correlations between energy and macronutrient intake and metabolic risk variables in three FTO-gene-allele groups. Results: Overall, 198 adult subjects with type 2 diabetes (T2D) were recruited and categorized into three genotype groups: TT, AA and AT with the mean age of 49.7 ±9.7, 49.3 ±10.6 and 50.2 ±8.8 years, respectively. A close association was observed between the minor allele A at rs9939609 and type 2 diabetes. A linear correlation was observed between diet and metabolic profile markers such as BMI, waist circumference, blood pressure, and lipid profile among high-risk alleles AA. The associations of energy intake and percent level of carbohydrate and protein intake with metabolic syndrome were significantly higher among risk alleles AA (P<0.05). However, the majority of the biochemical parameters and dietary components were found to be statistically insignificant (p>0.05). Discussion: Genetic profile is likely to affect both dietary habits as well as the association between diet and metabolic syndrome markers. This study concludes that diet-disease associations are more prominent in individuals having risk alleles AA as compared to protective alleles TT and heterozygous alleles AT.