Polymorphisms in various genes controlling appetite and metabolism predispose to obesity under certain dietary conditions. The percentage of obesity that can be attributed to genetics varies widely, depending on the population examined, from 6% to 85%.[6] As of 2006, more than 41 sites on the human genome have been linked to the development of obesity when a favorable environment is present.[7] The involvement of genetic factors in the development of obesity is estimated to be 40–70%. Some of these obesogenic or leptogenic genes may influence obese individuals response to weight loss or weight management.[8]