PSEN1 and Alzheimer disease: Other than the widely recognized APP duplications, deletions of exon 9 in PSEN1 have been discovered in families affected by a variant of AD with spastic paraparesis and unusual plaques (Table 1; Crook et al., 1998; Smith et al., 2001), and 10 novel CNVs overlapping a set of genes, including A2BP1, ABAT, CDH2, CRMP1, DMRT1, EPHA5, EPHA6, ERMP1, EVC, EVC2, FLJ35024, and VLDLR, were found to co-segregate with disease status from 261 early-onset familial AD families (Hooli et al., 2014).