According to an autosomal DNA study (from 2003) focused on the composition of the Brazilian population as a whole, "European contribution [...] is highest in the South (81% to 82%), and lowest in the North (68% to 71%). The African component is lowest in the South (11%), while the highest values are found in the Southeast (18%-20%). Extreme values for the Amerindian fraction were found in the South and Southeast (7%-8%) and North (17%-18%)". The researchers were cautious with the results as their samples came from paternity test takers which may have skewed the results partly.