This paper reviews current data concerning the role of the genotype in human variation in fat distribution and its contribution in regulating fat deposition in various regions of the body, primarily the lower trunk area. After statistical control over age, gender and total amount of subcutaneous fat, one finds an additive genetic effect of about 20-25% of remaining human variance in amount of lower trunk fat and in the relative proportion of lower trunk versus extremity fat. In spite of such a moderate genetic effect in fat distribution, the preferential site of fat deposition when exposed to chronic overfeeding is largely determined by one's genotype. Characteristics of regional adipose tissue metabolism and morphology are probably involved in mediating some of these genetic effects but other regulatory mechanisms are undoubtedly implicated.