Genetic Variants Associated with Calorie and Macronutrient Intake in a Genome-Wide Association Study

ABSTRACT

There has been no genome-wide association study (GWAS) for macronutrient intake as a quantitative trait. To explore genetic loci associated with total calorie and macronutrient intake, genome-wide association data of autosomal single nucleotide polymorphisms (SNPs) from Korean adults were analyzed. We conducted a GWAS in 3,690 men and women aged 40 to 60 years from an urban population-based cohort. At the baseline examination (June 18, 2001 through January 29, 2003), DNA samples of the study subjects were collected and analyzed for genotyping. The information of average daily consumption of total calorie, carbohydrate, protein, and fat was obtained from a semi-quantitative food frequency questionnaire and transformed by natural logarithm for analyses after adjustment of calorie intake. Using multivariate linear regression analysis adjusted for age, sex, and height, we tested for 352,021 SNPs and found weak associations, which do not reach genome-wide association significance, with calorie and macronutrient intake. However, a number of SNPs were found to have potential associations with macronutrient intake; in particular, signals in SORBS1 and those in PRKCB1 were likely associated with carbohydrate and fat intake, respectively. We observed an inverse association between the minor allele of the SNPs in these genes and the amount of consumption of carbohydrate or fat. Our GWAS identified loci and minor alleles weakly associated with macronutrient intake. Because SORBS1 and PRKCB1 are reportedly associated with the metabolism of glucose and lipid as well as with obesity-related diseases, further investigations on biological and functional roles of polymorphism of these genes in the relation to macronutrient intake are warranted.