Random-effects meta-analysis demonstrated that blood TNF-α (Hedges’ g = 0.655; 95% CI, 0.284 to 1.026; p = 0.001), TNF receptor 1 (TNFR1; Hedges’ g = 0.741; 95% CI, 0.474 to 1.007, p < 0.001), IL-6 (Hedges’ g = 0.25; 95% CI, 0.074 to 0.427; p = 0.005), IL-1β (Hedges’ g = 0.296; 95% CI, 0.017 to 0.575; p = 0.038), IL-8 (Hedges’ g = 0.449; 95% CI, 0.258 to 0.641; p < 0.001) and vascular endothelial growth factor (VEGF; Hedges’ g = 0.891, 95% CI: 0.298, 1.485; p = 0.003) levels were significantly elevated in patients with ALS compared with control subjects (Figs 2–4 and Table 1). This evidence concerns the gene VEGFA and amyotrophic lateral sclerosis.