Of the 26, four are known to have genetic links to CNS disorders; ADD3 (cerebral palsy with spastic paraplegia), SLC1A3 (Episodic ataxia, type 6), NOTCH3 (Cerebral arteriopathy with subcortical infarcts and leukoencephalopathy 1) and ABCA1 (GWAS association with AD; https://omim.org/). Here, ADD3 is linked to Alzheimer disease.