Native American ancestry proportions and age of admixture in the Quebec population sample by different methods and using different reference populations (see Table S2).

aFor ADMIXTURE, Siberians were used as a third reference population,. whereas IBD sharing and ALDER, used only Native Americans as a single reference population.bFor HAPMIX, 50 samples were randomly selected from each of the reference populations to match the Native North American sample size.