Glucokinase gene promoter-30G>A polymorphism: a cross-sectional association study with obesity, diabetes Mellitus, hyperlipidemia, hypertension and metabolic syndrome in an Iranian hospital

Objective A -30G>A single nucleotide polymorphism in the promoter region of the glucokinase gene has been previously associated with obesity, insulin resistance and diabetes. The present study aimed to evaluate the association of this polymorphism with obesity and its comorbidities in a population from Northeast Iran. Methods Five hundred and forty-two subjects aged 18 to 65 years were included in the study and divided into normal (BMI<25, n=220), overweight (25<BMI<30, n=135) and obese (BMI>30, n=187) groups. All subjects were genotyped for the -30G> A polymorphism using the polymerase chain reaction-restriction fragment length polymorphism technique. Results The genotypes and allele frequencies of the three groups did not differ significantly (p>0.05). When the study population was categorized according to diabetes mellitus, hyperlipidemia, hypertension and metabolic syndrome status, no significant difference in -30G>A genotypes and alleles was found between the subgroups with and without these disorders ( p>0.05), apart from a significantly higher frequency of the G allele in the hyperlipidemic vs. non-hyperlipidemic subgroup ( p<0.05). Conclusion The findings of the present study do not support an association between the -30G>A polymorphism and high body mass index in the Iranian population.