Linkage disequilibrium patterns and genetic structure of Amerindian and non-Amerindian Brazilian populations revealed by long-range X-STR markers

FP LEITE, S SANTOS, E RODRÍGUEZ, S CALLEGARI-JACQUES, DA DEMARCHI, L TSUNETO, M PETZL-ERLER, FM SALZANO, M HUTZ

AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY

Wiley-Liss

Lugar: New York; Año: 2009 vol. 139 p. 404 - 412

0002-9483

The extent of X-chromosome linkage disequilibrium (LD) was studied in a southern Brazilian population, and in a pool of samples from Amerindian populations. For this purpose, 11 microsatellites, located mostly in a Xq region comprising ~86 Mb wasinvestigated. The lower Amerindian gene diversity associated with significant differencesbetween the populations studied indicated population structure as the main cause for thehigher LD values in the Amerindian pool. On the other hand, the LD levels of the non- Amerindian Brazilian sample, although less extensive than that of the Amerindians, wereprobably determined by admixture events. Our results indicated that different demographic histories have significant effects on LD levels of human populations, and provide a first approach to the X-chromosome ancestry of Amerindian and non-Amerindian Brazilian populations, being valuable for future studies involving mapping and population genetic studies.