Prediction of Response to GLP-1/GIP Receptor Agonists in Obesity Using Genetic Risk Score and SNP Profiling: A Prospective Cohort Study.

Obesity is a chronic disease resulting from complex interactions between genetic, environmental, and behavioral factors. Genetic influences account for a substantial proportion of obesity susceptibility, with heritability estimates ranging from 40% to 75%. Genome-wide association studies have identified numerous genetic variants associated with body mass index, appetite regulation, energy homeostasis, and metabolic function.

Glucagon-like peptide-1 (GLP-1) receptor agonists and dual GIP/GLP-1 receptor agonists have significantly improved the pharmacological management of obesity. Semaglutide and tirzepatide produce clinically meaningful weight reduction and improvement in metabolic outcomes. However, treatment response varies considerably among individuals, and the factors underlying this variability are not fully understood.

Genetic Risk Scores (GRS), which combine the effects of multiple obesity-related genetic variants, have emerged as potential tools for predicting disease risk and therapeutic response. Their role in predicting response to anti-obesity pharmacotherapy remains largely unexplored.

This prospective observational cohort study aims to evaluate whether a GRS and selected obesity-related single nucleotide polymorphisms (SNPs) can predict weight loss response to semaglutide or tirzepatide in adults with obesity.

Eligible participants initiating treatment with semaglutide or tirzepatide will be consecutively recruited and followed for six months. At baseline, demographic, clinical, anthropometric, biochemical, and genetic data will be collected. Approximately 18 obesity-related SNPs, including variants in genes involved in appetite regulation, energy balance, and glucose metabolism, will be analyzed. An additive Genetic Risk Score will be calculated based on the cumulative number of risk alleles.