Association of polymorphic variants of the leptin gene with anthropometric and biochemical parameters in adolescents with different weight status

The leptin gene (LEP) is considered as a potential candidate gene affecting metabolic disorders associated with predisposition to overweight and obesity. The aim of the study. To search for single nucleotide polymorphisms (SNP) of the leptin gene and to assess their relationship with anthropometric and biochemical parameters in Russian and Buryat adolescents with different weight status. Materials and methods. The study included adolescents of two ethnic groups – Caucasoid (Russians) and Mongoloids (Buryats) – aged 11–17 years (mean age 14.8 ± 0.45 years) with different weight status. We assessed anthropometric parameters, determined biochemical parameters and leptin level in the blood plasma, and sequenced the leptin gene fragment localized in the 128253475–128255334 region (1859 bp) of this gene using the Sanger method. Results. The sequencing of the leptin gene fragment identified 10 single nucleotide substitutions (rs28954118, rs3828942, rs759854910, rs199893150, rs7788818, rs144755411, rs917105894, chr7:128255051, chr7:128255092, chr7:128254681), two of them (rs28954118, rs144755411) had a correlation with biochemical and anthropometric parameters. In the group of Russian adolescents with overweight and/or obesity, the carriers of the AT variant of rs28954118 had statistically significantly higher levels of triglycerides (TG), very low density lipoprotein (VLDL) cholesterol, skin fold thickness on the abdomen and fat mass percentage compared with carriers of the AA genotype. In the control group of Buryat adolescents, the parameters of waist width, skin fold thickness on the hip and waist width/height ratio are statistically significantly lower in carriers of the CT variant of rs144755411 compared with carriers of the CC genotype. Conclusion. AT genotype of rs28954118 was identified only in Russian adolescents with overweight and/or obesity, and was accompanied with statistically significantly high values of TG, VLDL cholesterol, skin fold thickness on the abdomen and fat mass percentage. The SNPs we identified do not affect the concentration of leptin.