Admixture mapping might provide novel insights into one potential source of the differential prevalence of alcohol dependence between EA and AA (Seldin, Pasaniuc, & Price, 2011). One study found that the degree of African admixture is correlated with alcohol dependence; and those with alcohol dependence have less African ancestry (Zuo et al., 2009). Since admixture in AA occurred relatively recently (usually <10 generations), only a small number of recombination events have likely occurred and the size of ancestry-specific regions is expected to be large. That is, the average size of an African ancestry block in AA is about 17 centimorgans (Patterson et al., 2004). Thus, a much smaller number of genetic markers would be needed to tag such regions than is required in a typical GWAS. Admixture mapping has been successfully applied to other traits, e.g. blood pressure, obstructive sleep apnea, systemic lupus erythematosus, etc., (Molineros et al., 2013; Sofer et al., 2017; Wang et al., 2019; Winkler, Nelson, & Smith, 2010); however, to our knowledge, it has not been applied to the study of alcohol dependence and related phenotypes in AA.
