MUL1 and amyotrophic lateral sclerosis: Additionally, PROT‐a‐638 (COX5B), PROT‐a‐1969 (MUL1), and PROT‐a‐1970 (MUL1) exhibited lower levels associated with ALS (IVW: OR = 0.9280, 95% CI 0.8808–0.9776, p = 0.0049; IVW: OR = 0.9272, 95% CI 0.8728–0.9851, p = 0.0144; IVW: OR = 0.9159, 95% CI 0.8613–0.9740, p = 0.0051).