MTHFR and infection: Many potential risk factors have been identified that include genetic disorders such as α1-antitrypsin (α1-AT) deficiency [10–12], connective tissue disease [13–15], MTHFR TT genotype [16], homocysteine concentration within the serum [16,17], history of migraine [18–20], variations in cardiac/cervical vessel anatomy [21–25], infection [10,19], oral contraceptive use [10,18,20], and trivial trauma [26–30].