EDA2R and early-onset autosomal dominant Alzheimer disease: In the forward direction MR (circulating protein concentration → dementia; Supplementary Table 4; Supplementary Figs 16–19), there was evidence of a potential causal link from circulating EDA2R to Alzheimer’s disease (FinnGen 2023; coefficient [β]; standard error [se]: 0.259 [0.096]; P = 0.007, based on the inverse-variance weighted [IVW] method), and ACD [β (se): 0.232 (0.110); P = 0.035, based on IVW].