Background. Fast growth rate during infancy may increase obesity risk. Obesity development is influenced by both external (mother anthropometry, climate, etc.) and internal factors (genetic predisposition). We aimed at studying the genetic polymorphism effect on the growth rate of infants from mothers with and without obesity in warm climate.
Methods. Anthropometric indices of 100 infants from Astrakhan were measured from birth to 12 months of age and Z-scores weight for age (WAZ), length for age (LAZ), weight for length (WLZ) and body mass index (BMI) for age (BAZ) (ANTHRO, 2005) at birth and their changes (delta) from 0 to 12 months were calculated. Infants were genotyped by the rs9939609 polymorphism of the FTO gene by real time PCR. Results were analyzed by the SPSS 20. The differences were considered statistically significant at p<0.05. 
Results. For mothers with obesity (n=40), infants with the AA genotype of rs9939609 had higher body weight, BMI, WAZ, LAZ and BAZ at birth compared with carriers of the AT genotype (Fig.1), and a significantly lower growth rate for 1, 3, 6, and 9 months of life (lower values of delta WLZ, BAZ and WAZ) (Fig. 2). Growth rate increase tendency was observed in these infants from 9 to 12 months of life (Fig.3). In mothers without obesity, the same effect of genotype on infants' growth rate was observed, but without significance.
Conclusion. The AA genotype of the rs9939609 polymorphism in combination with mother obesity contributes to increased intrauterine fetus weight accumulation, possibly because of warm climate. Increased birth weight might be inhibiting growth of infants up to 9 months of age.

OBESITY IN WOMEN AND THE GROWTH RATE OF THEIR INFANTS: THE ROLE OF GENETIC POLYMORPHISM AND ENVIRONMENTAL FACTORS