By Nancy LapidApril 10 (Reuters) – Weight-loss responses to GLP-1 obesity drugs, and risks of side effects, may be linked to genetic variants, according to a study conducted by DNA-testing service 23AndMe.The study of nearly 28,000 23AndMe users who reported taking the weight-loss drugs found that a mutation in GLP1R, the gene for the protein targeted by GLP-1 drugs, is modestly but significantly associated with increased efficacy of the medications, researchers reported in Nature.AdvertisementAdvertisementPeople carrying one copy of that variant lost, on average, 1.7 pounds (0.76 kilograms) more over a median of eight months of treatment than people who had no copies. People carrying two copies of the variant lost some 3.3 pounds more.Mutations in the GLP1R gene and in another gene – GIPR, which is related to insulin secretion and energy production – were associated with medication-related nausea or vomiting.The GIPR side effect association was only seen in people using Eli Lilly’s tirzepatide, however. People carrying that variant were 83% more likely than non-carriers to vomit after taking tirzepatide, sold as Mounjaro for diabetes and Zepbound for obesity.The genetic effect on weight loss was relatively small, researchers acknowledged.AdvertisementAdvertisement“These findings provide direct genetic evidence that variation in the drug-target genes contributes to inter-person variability in response and lay the foundation for precision medicine approaches in the treatment of obesity,” they said.GLP-1 HEART BENEFITS MAY BE DISTINCT FROM OBESITY EFFECTSThe cardiovascular benefits derived from GLP-1 drugs may b …
