Mestriner_1976_Am.J.Hum.Genet_28_257

Significant variation in the frequency of Esterase D isoenzymes was found in 1,070 individuals belonging to eight South American Indian tribes. The Es D1 allele shows frequencies varying from .36 to 1. A region of low prevalence of this allele seems to exist in northern Brazil, involving the Parakanan, Gorotire, and Kraho. The intratribal variation observed in eight Yanomama villages located in Brazil was not exceptional.