APOE and Schnyder corneal dystrophy: Based on the evidence accrued until 2014, a group of researchers forming the SCD-Initiative proposed the “SCD-plus criteria” as an enrichment strategy for the likelihood of preclinical AD in individuals with SCD [9], comprising (a) Subjective decline in memory rather than other domains, (b) onset of SCD within the last 5 years, (c) age of onset ≥ 60 years, (d) particular concerns associated with SCD, (e) the feeling of worse performance than others of the same age group, (f) confirmation of perceived cognitive decline by an informant, and (g) the presence of the APOE e4 genotype.