Sequencing of a fragment of the leptin gene in adolescents with different weight status

Abstract

Background. Obesity is a significant social problem among the population of the world. The leptin gene (LEP) is currently considered as a potential candidate gene influencing metabolic disorders associated with predisposition to overweight and obesity. Leptin plays an important role in body weight homeostasis by influencing food intake and energy expenditure and maintaining constant energy stores. A defect in the leptin gene may be one of the causes of obesity and, as a result, of various obesity-associated pathologies. The aim of the study. To search for single-nucleotide polymorphisms (SNP) of the leptin gene in adolescents with different weight status. Methods. The study involved 20  adolescents aged 11–17  years with normal body weight and  overweight/obesity. Research methods: assessment of clinical status with  anthropometry; Sanger sequencing of the leptin gene fragment localized in the  intron of this gene – (5’-AGCCTTGTTTTCATCATCTGGA, 3’-TGGGAGGAATCGCTCTCAGA). We also carried out bioinformatic processing of sequencing results. Results. As a result of the study, the optimal conditions for amplification of the 891 bps leptin gene region were selected for the above mentioned primer pair of the LEP gene (s16_L891, s16_R891). Based on the results of sequencing, 45 single nucleotide substitutions of the LEP gene were identified, including 23 single nucleotide substitutions which were not previously registered in GenBank. In the group of adolescents with overweight and obesity, 14 unregistered single nucleotide substitutions of the LEP gene and 13 registered SNPs were identified in the GenBank database. In the group of adolescents with normal body weight, these SNPs were not found.