[Genetic background in common forms of obesity - from studies on identical twins to candidate genes of obesity].

Common obesity is a result of interaction between genes and environmental/lifestyle factors, with heritability estimates 40-70%. Not only the susceptibility to obesity but also the success of weight management depends on the genetic background of each individual. This paper summarizes the up-to-date knowledge on genetic causes of common obesities. Introduction of genome-wide association studies (GWAS) led to an identification of a total of 32 variants associated with obesity/BMI and 14 with body fat distribution. Further, a great progress in revealing the mechanisms regulating the energy balance was also noted. However, the proportion of explained variance for BMI is still low, suggesting other mechanisms such as gene-gene and gene-environment interactions, rare gene variants, copy number variants polymorphisms, or epigenetic modifications and microRNAs regulating gene transcription. In summary, we present results of our studies on obesity risk variants in Czech adults, children and adolescents including those evaluating the influence of selected gene variants on the outcomes of weight management.