MATERIAL AND METHODS 152 obese children aged 6-18 years were genotyped for the LCT/MCM6 genes (RT-PCR, Synevo, Ukraine). The main group (n = 77) according to the IDEFICS 2014 recommendations was represented by children with MUO. The control group (n = 75) consisted of children with metabolically healthy obesity. Whole genome sequencing (NGS, CeGat, Germany) was performed in 27 children of the main and 15 children of the control group. To verify the results, bioinformatics analysis, analysis of nominal data, calculation of Cramer’s criterion (V), Pearson’s randomness factor (C), and the normalized value of Pearson’s coefficient (C’) were used.