Individuals with TT genotypes for MTHFR C677T had 13% (adjusted OR = 1.13, 95% CI 1.09–1.17) higher risks of any stroke, with a 2-fold stronger association with intracerebral haemorrhage (n = 3189 cases; 1.24, 1.17–1.32) than for IS (n = 8762; 1.11, 1.07–1.15). The gene discussed is MTHFR; the disease is stroke disorder.