What do studies say about FTO Genetik?

The FTO gene (e.g., rs9939609) is the most consistently replicated genetic risk factor for obesity. Carriers of the risk allele (A) have on average ~0.4 kg/m² higher BMI and a 20–30 % increased obesity risk. However, the effect per allele is small and strongly modulated by lifestyle (diet, physical activity). The association is confirmed by numerous GWAS and meta-analyses (evidence: human-strong). Importantly, a single SNP cannot diagnose obesity. The FTO variant likely affects satiety and food choice rather than basal metabolic rate. Direct-to-consumer tests often overstate the risk. Clinical relevance is limited; lifestyle interventions work regardless of genotype. In Germany, such tests fall under the Genetic Diagnostics Act (GenDG) – they are not diagnostic and prohibited for minors.