On the use of Chinese population as a proxy of Amerindian ancestors in genetic admixture studies with Latin American populations

We read the recent article of Magalhães da Silva et al1 reporting the correlation between biogeographic ancestries, estimated using 30 ancestry informative markers(AIMs), and self-reported skin color in two different Brazilian Northeastern populations (Fortaleza and Salvador, capitals of the states of Ceará and Bahia, respectively). The authors observed that African ancestry is more correlated in the sample from Salvador than in the one from Fortaleza and that the use of different African populations as proxies of the Brazilian’s African ancestors may influence the results.