MTHFR and hyperhomocysteinemia: It is also conceivable that the impact of homocysteine on hemorrhagic stroke outcomes is moderated by factors such as the extent of hematoma expansion, the presence of intraventricular hemorrhage, or patient-specific responses to hyperhomocysteinemia, such as variations in the methylenetetrahydrofolate reductase gene, which could influence individual susceptibility to the detrimental effects of high homocysteine levels (21–23).