Dogs and humans share obesity genes

Obesity is a global health problem mainly attributed to environmental and lifestyle factors such as diet, low physical activity or socioeconomic factors. However, genetic factors also considerably contribute to weight-gain susceptibility. Although large-scale population genomic studies in humans have identified >1,000 loci associated with body mass index, effectively narrowing down candidate genes for further mechanistic studies has been challenging. Pet dogs represent a valuable model for studying the genetic basis of obesity because, like humans, they are experiencing an obesity pandemic (40-60% of pet dogs are classified as overweight or obese), and because modern breeds are genetically homogenous, making trait mapping highly tractable. To identify obesity genes, Wallis and colleagues performed a canine genome-wide association (GWAS) study for body condition score—a measure of obesity—in 241 Labrador retrievers, a dog breed prone to obesity. From the GWAS, they identified the gene DENN domain containing 1B (DENND1B) as an obesity gene in dogs and confirmed its relevance to human obesity using data from human studies. These findings demonstrate the benefits of studying complex diseases, including obesity, in nontraditional animal models, such as the dog.

Original reference: Wallis, N.J. et al. Science 387, eads2145 (2025)