Ancestry analysis in rural Brazilian populations of African descent.

Rural communities comprise around 20% of Caribbean and South American populations, but are under-represented in autosomal marker databases. That deficiency is problematic for forensic genetics, as it relies on accurate descriptions of genetic variation and population structure. Brazilian populations were shaped by an intense, complex and heterogeneous process of admixture encompassing mainly Amerindians, Sub-Saharan Africans and Europeans.