A new world syndrome of metabolic diseases with a genetic and evolutionary basis

Currently, many Amerindian peoples, including European- Amerindian admixed groups such as Mexicans, are experiencing a major epidemic of a series of diseases which includes a tendency to become obese at an early adult age, adult onset diabetes mellitus, the formation of cholesterol gallstones, and gallbladder cancer, especially in females. Other cancer sites, and morbid consequences of these primary disorders, also occur at elevated rates. This epidemic has begun, or at least increased dramatically since World War II, and seems to be due to an interaction between susceptible Amerindian genotype(s) and some recently changed aspect of the environment, probably involving dietary components. This paper reviews the epidemiology of this New World Syndrome (NWS), quantifying incidence, prevalence, and risk in susceptible genotypes. This pattern is distinct from the rise of similar diseases associated around the world with “westernization.” The susceptible genes probably arose by virtue of a selective advantage during or before the initial peopling of the Americas.