Evolutionary Responses to a Constructed Niche: Ancient Mesoamericans as a Model of Gene-Culture Coevolution

Hünemeier, Tábita; Amorim, Carlos Eduardo Guerra; Azevedo, Soledad; Contini, Veronica; Acuña-Alonzo, Víctor; Rothhammer, Francisco; Dugoujon, Jean-Michel; Mazières, Stephane; Barrantes, Ramiro; Villarreal-Molina, María Teresa; Paixão-Côrtes, Vanessa Rodrigues; Salzano, Francisco M.; Canizales-Quinteros, Samuel; Ruiz-Linares, Andres; Bortolini, Maria Cátira

Based on studies with blood groups and other classical genetic polymorphisms, J. V. Neel and F. M. Salzano were pioneers in identifying complex population processes highly dependent on cultural factors in Native Americans (e.g., fission-fusion dynamic; [18] ). Other examples are related to the coevolution of genes and languages [19, 20] , but only two more recently reported examples might be associated with positive selection: (1) Tovo-Rodrigues et al. [21] investigated the distribution of D4 dopamine receptor (DRD4) alleles in several South Amerindian populations and found a significant difference in the allelic distributions between huntergatherers and agriculturalists, with an increase of the 7R allele among the former; and (2) Acuñ a-Alonzo et al. [22] showed that the 230Cys allele (Arg230Cys, rs9282541) of the ATP-binding cassette transporter A1 (ABCA1) gene, which was previously associated with low HDL-cholesterol levels and obesity-related comorbidities, was exclusively present in Native American and mestizo individuals. These authors verified that cells expressing the ABCA1*230Cys allele showed a 27% cholesterol efflux reduction, confirming that this Native American autochthonous variant has a functional effect in vitro. Other investigations have shown that the presence of ABCA1*230Cys explains almost 4% of the variation in plasma HDL-C concentrations in Mexican admixed populations [23] . This variation in HDL-C concentration was the highest one associated with a single nucleotide polymorphism (SNP) among different continental populations in these genome-wide association studies, corroborating its functionality [23] .