Background: The minor allele frequencies (MAFs) of the FTO gene vary substantially among different ethnic groups, and this variation may explain, to some degree, the differences between estimates of the effects of these alleles on body fat distribution indicators.
Objectives: The aim of this study was to investigate the prevalence of fat mass and obesity associated (FTO) gene variants characterizing the structure of FTO haplotypes in a large Polish population, and to examine the influence of FTO gene variants on body fat distribution among metabolically obese normal weight (MONW) individuals, i.e. those with a normal BMI and visceral obesity.
Material and methods: A total of 854 non-obese individuals aged from 20 to 40 years, residing in three different regions in Poland, were studied. All the patients from this group were genotyped for four FTO gene variants (rs9939609, rs9930506, rs1421085 and rs1121980). Simultaneous identification of all single nucleotide polymorphisms (SNPs) was conducted using the minisequencing method with a pair of designed specific primers.
Results: Over 90% of the diplotypes contain only the two most common haplotypes, in three combinations of haplotype pairs: CTAT/CTAT comprised 26.9% in women and 30.9% in men; CTAT/TCGA comprised 45.0% in women and 44.4% in men; and TCGA/TCGA comprised 19.3% in woman and 14.8% in men. The analysis of the variance in body fat distribution parameters shows no statistically significant differences between the three common haplotype pairs in either men or women.
Conclusions: The young Polish population is characterized by two disparate haplotypes of common FTO gene variants: TCGA (a risk SNP haplotype), and CTAT (a protective haplotype). No significant differences were found between fat distribution indicators in relation to haplotypes in either women and men.