Science Daily reports that "New research finds around a quarter of Labrador retriever dogs face a double-whammy of feeling hungry all the time and burning fewer calories due to a genetic mutation."
Labs and Flat Coats that carry this gene found that the POMC mutation altered "a pathway in the dogs' brains associated with body weight regulation. The mutation triggers a starvation signal that tells their body to increase food intake and conserve energy, despite this being unnecessary."