Another approach to address ancestry in genetic studies is the use of ancestry informative markers (AIMS) which are a fixed small set of markers (1500–5000) shown to have high differentiation between ancestral populations. AIMS are useful when no GWAS data are available such as in candidate gene or target genotyping for replication studies. There is not perfect agreement between SIA and AIMs as SIA may provide more information on social and environmental exposures while AIMS may provide a better estimate of ancestry.6 However, if GWAS data are available, limiting the ancestry analyses to a small fixed set of markers is not ideal.5,6
