Consistent with this, the MAPT A152T and S318L mutations were observed to occur 3× as frequently in AD cases compared to controls in an Ibero-American cohort, with Spanish and Uruguayan ancestry (Jin et al., 2012), with additional missense variants identified in exons 4a, 7, and 10 with unknown effects (Jin et al., 2012). Here, MAPT is linked to Alzheimer disease.