Aim of investigation. Investigation of association of leptin receptor (LEPR) gene Gln223Arg polymorphism with obesity and non-alcoholic fatty liver disease (NAFLD).Material and methods. Overall 107 patients with NAFLD, 81 patient with alcoholic liver disease (ALD) and 117 patients without liver diseases (control group) were investigated. Obesity criterion was body the body mass index (BMI) ≥30,0. Cholesterol and triglycerides serum levels were estimated by enzyme colorimetric method, leptin concentration — by immunoenzyme method. Genotyping for LEPR Gln223Arg gene polymorphism was carried out by allele — specific polymerase chain reaction.Results. In control group and ALD patients no correlation of obesity with LEPR Gln223Arg gene polymorphism was revealed. In NAFLD patients without obesity Arg223Arg genotype, as well as 223Arg allele, was less frequent, than in control group — 3 times (P<0,05) and 1,5 times (P<0,05) respectively. Frequency of this genotype / allele was also significantly less in NAFLD group without obesity, than in those with obesity. Mean serum cholesterol level at NAFLD was higher, than at ALD (Р <0,05), and in Gln223Gln genotype carriers this parameter was highest in comparison to that parameter in other groups. At NAFLD patients 223Arg variant was less frequent (49,5%), than 223Gln variant, in contrast to other groups. Allelic frequency of 223Gln in women with NAFLD was 1,5 times higher (P<0,05) , than in women with ALD, and 1,3 times higher (P<0,05), than in women of control group. Frequency of Gln223Gln genotype in women with NAFLD was higher than that in women with ALD 1,5 times (Р<0,01), in women of control group — 1,3 times (Р<0,05) and in men with NAFLD — 3 times (Р=0,05) respectively.Conclusions. Carriage of 223Gln variant of LEPR Gln223Arg gene polymorphism can promote increase of cholesterol level and development of non-alcoholic fatty liver disease in absence of obesity as well, is especial in women
