IL18 and glycine encephalopathy: Genetically predicted increased levels of hepatocyte growth factor and decreased levels of eotaxin and interleukin-18 are associated with an increased risk of GCE (OR = 1.904, 95% CI = 1.019–3.561, p = 0.044; OR = 0.641, 95% CI = 0.417–0.984, p = 0.042; OR = 0.482, 95% CI = 0.251–0.927, p = 0.046).