Methods for detecting and correcting for population stratification

Population stratification (PS) is a primary consideration in studies of the genetic determinants of human traits. Failure to control for it may lead to confounding, causing a study to fail for lack of significant results or resources to be wasted following false-positive signals. Here we review historical and current approaches for addressing PS when performing genetic association studies in human populations. We describe methods for detecting the presence of PS including global and local ancestry methods. We also describe approaches for accounting for PS when calculating association statistics, such that measures of association are not confounded. This is particularly important since many traits are being examined in minority populations, populations that may inherently feature PS.