Obesity: exploiting genomes for novel insights

When so many people share sedentary lifestyles and ready access to junk food, why do only some become fat? Evidence shows that 40-70% of the difference is down to genes, but only a fraction of those responsible are known. I study pet dogs to find links between genes and obesity. Dogs are commonly obese, share genes and lifestyles with humans and selective breeding means they have unusual genetics which can be helpful when trying to identify obesity genes. Labradors are prone to obesity and they are notoriously obsessed with food. I recently showed that a quarter of Labradors have a genetic mutation, known as POMC, which breaks a brain mechanism that usually switches off hunger.

I intend to study Labradors to learn about how the affected gene controls the body’s energy balance. The affected part of POMC is important in people but different in rodents so it has been difficult to study before. I will also test several other breeds of dog to find new obesity genes. Early results show that my approach works and the genetic areas identified are important in humans too.

Comparing dogs and humans will identify genes influencing obesity in both which can be targeted for future study with the aim of understanding the biology obesity and how to treat it.