MR suggested causal effects of higher LDL-c (ORIVW = 1.085, 95%:CI 1.008–1.168, pFDR = 0.0406), total cholesterol (ORIVW = 1.081, 95%:CI 1.013–1.154, pFDR = 0.0458) and apolipoprotein B (ORIVW = 1.104, 95%:CI 1.041–1.171, pFDR = 0.0061) increasing ALS risk, and higher apolipoprotein B level increasing FTD risk (ORIVW = 1.424, 95%CI 1.072–1.829, pFDR = 0.0382). Here, APOB is linked to frontotemporal dementia.