ABCA1 and Alzheimer disease: Our analysis of CNVs in a Turkish dementia cohort extends previous reports of CNVs overlapping the genes ZNF804A, SNORA70B, USP34, XPO1, and a locus on chromosome 9 which includes a cluster of olfactory receptors and ABCA1. With regard to ZNF804A, both duplications and deletions have now been reported in AD.