TRAPPC6A and Alzheimer disease: In addition, some genes showed extensive cross-tissue effects on AD, such as AD was associated with the expression of APOE, CEACAM19, CLPTM1, DMWD, KAT8, PRSS36, PVRL2, SIX5, TRAPPC6A, PPP1R13L and PPP1R37 in at least three tissues.