Jeffrey M. Friedman

My laboratory studies the mechanisms by which genes contribute to differences in food intake and body weight. In the absence of the hormone leptin, humans and other mammals become massively obese. Such individuals also manifest a dramatic increase in food intake and develop many other abnormalities that are corrected by injections of leptin. We are investigating the mechanisms by which leptin reduces weight in this and other settings. We are also exploring the ways that changes of the blood levels of this single molecule can alter a complex behavior, namely how much an individual eats. Other efforts are aimed at establishing the genetic basis of obesity amongst the residents of Kosrae, a Pacific island with a high prevalence of this condition.