Given the multiplicative effects of SCD and APOE ɛ4 status on AD risk [14], and the fact that no cure or disease-modifying drug has become widely available for AD treatment, it is imperative to examine both risk factors (i.e., SCD and APOE) in order to better understand those at risk for the development of AD. The gene discussed is APOE; the disease is Schnyder corneal dystrophy.