The primary findings of this paper are (i) multiple PICALM isoforms are expressed in human brain, (ii) consistent with immunohistochemistry results that PICALM is commonly found in microvessels, expression of total PICALM and the abundant D13-PICALM is positively correlated with the expression of microvessel mRNAs, (iii) total PICALM expression correlates modestly with the AD-associated SNP rs3851179, (iv) D2-4 PICALM was associated with AD status and an exon five SNP, rs592297, which is in linkage disequilibrium with rs3851179 (r2 = 0.34). Here, PICALM is linked to Alzheimer disease.