CD8A and amyotrophic lateral sclerosis: In the reverse MR results of immune cells with ALS, there are causal relationships between ALS and two types of immune cells including the expression levels of CD3 on Effector Memory CD8+ T cells and the expression levels of CD3 on CD4+ T cells, with IVW results of the former (p= 3.79E-02; OR 95%CI= 0.78 (0.62,0.99)) and the latter (p= 3.77E-02; OR 95%CI= 0.81 (0.67,0.99)) correspondingly.