BACKGROUND & OBJECTIVES:This study investigates the association of two potential Fat mass and obesity associated gene (FTO) gene polymorphisms (rs9939609 and rs918031) as potential predictors of type 2 diabetes (T2D) in obese Iraqi population and their metabolic effects on hyperglycemia and insulin sensitivity. MATERIALS & METHODS:The study included 400 participants with obesity & T2D, with a matching 400 obese non-diabetic cohort. Venous blood samples were collected for DNA extraction. Using specific primers and restriction enzymes, genotyping was performed to identify the various alleles for each gene. The genotype and allele frequencies determined by multinomial logistic regression analysis for FTO single nucleotide polymorphisms (rs9939609) among all the study groups. RESULTS:There is a two-fold increase in the risk of T2D within the homozygous genotype (TT) group (OR = 2.43, CI 95% 3.57-11.2, P ≤ 0.001) as compared to the wild type (TA). In addition, there was a significantly higher level of the minor allele genotype (T) in T2D patients when compared to the control group, (P ≤ 0.001). CONCLUSION:We conclude that the FTO rs9939609 genotype significantly affect the development of insulin resistance, therefore the future occurrence of T2D, in obese individuals.