HLA-DRB1 and early-onset autosomal dominant Alzheimer disease: At P<2.5×10−6, we found significant associations with risk of Alzheimer’s disease for APOC1 (Z = 4.84, P = 1.29×10−6) and HLA-DRB1 (Z = 6.80, P = 1.05×10−11) that also passed permutation testing.