MTHFR and deep vein thrombosis: Variants in the genes for both intercellular adhesion molecule 1 (ICAM1) and cytoskeletal alpha-1-syntrophin (SNTA1) have also been associated with CeAD (232, 236), whereas associations between CeAD and metabolism involve variants in methylenetetrahydrofolate reductase (MTHFR), which regulates homocysteine levels (231), and alterations in homocysteine are associated with thrombosis and atherosclerosis that occur with deficiencies in folate, vitamin B6 and vitamin B12 (237).