Archaeology and the "thrifty" non insulin dependent diabetes mellitus (NIDDM) genotype

In recent decades, non-insulin dependent diabetes mellitus (NIDDM) has become a major public health problem in several parts of the world. A complex disorder, NIDDM is associated with an increased risk of blindness, coronary heart disease, peripheral vascular disease, and kidney failure (1). The epidemiology of NIDDM is providing new insights into many aspects of this disease, including prevalence, incidence, morbidity, and mortality (2). My objective is to explain the high prevalence of a NIDDM susceptible genotype(s) in several distinct populations: American Indians, Australian Aborigines, and Pacific Islanders. The susceptible genotype may have been selected into these populations because of unusually frequent food shortages that occurred during the initial colonization of 'new worlds'. NIDDM has been shown to have a strong genetic component (3) that may include a 'thrifty' genotype(s) (4,5). The 'thrifty' genotype(s) may have once allowed founding populations to survive feast' and 'famine' conditions for several generations. With an assured food supply and a sedentary lifestyle, however, the 'thrifty' genotype(s) becomes disadvantageous, leading to obesity, increased insulin resistance, beta cell decompensation, and NIDDM (3,6).