New genetic data on Amerindians from the Paraguayan chaco

New data on 17 blood group and protein genetic systems obtained among the A yoreo and Lengua Indians of Paraguay are presented. They include the first report on the red cell band-3 protein investigated among South American Ind ians. This information was integrated with previous results available for t hese two and four other groups. Five of the six populations reside in the C haco area, while the sixth was included as an outgroup living elsewhere in Paraguay. Four of the five Chaco tribes exhibit good genetic homogeneity, b ut the Ayoreo are somewhat different. The results confirm the Chaco as a di stinct biological (as well as cultural and economic) region, which should b e considered in evaluations of genetic variability among South American Ind ians. (C) 2001 Wiley-Liss, Inc.