The MFI of CD16–CD56+ on HLA-DR+ NK cells was also negatively associated with the risk of ALS in the IVW method (OR = 0.919, 95% CI = 0.854–0.989, P = 0.025) and MR-Egger (OR = 0.519, 95% CI = 0.321–0.838, P = 0.036; Supplementary Figure 1). The gene discussed is NCAM1; the disease is amyotrophic lateral sclerosis.