Methylenetetrahydrofolate reductase C677T polymorphism

Ulrich, C.M., et al., "Pharmacogenetics of Methotrexate Toxicity Among Marrow Transplantation Patients Varies with the Methylenetetrahydrofolate Reductase C677T Polymorphism," Blood, 98, 231-234 (2001). 

Ulrich CM, Yasui Y, Storb R et al. Pharmacogenetics of methotrexate toxicity among marrow transplantation patients varies with the methylenetetrahydrofolate reductase C677T polymorphism. Blood 2001 98 231-234. 

Sohn KJ, Croxford R, Yates Z et al. Effect of the methylenetetrahydrofolate reductase C677T polymorphism on chemosensitivity of colon and breast cancer cells to 5-fluorouracil and methotrexate. J... 

Methylenetetrahydrofolate reductase is an approximately 19,301 base pair gene with 11 exons and located on chromosome lp36.3 (2). Multiple polymorphic sites have been described, with the C677T and A1298G most often studied. As expected, allele frequency data varies by ethnicity The MTHFR C677T variant allele is present in 34% of Caucasians, 20% of Italians and Hispanics, 14% of African-Americans, and <1 % of Africans (3,4). The MTHFR A1298G allele is present in n%-36% of Western Europeans (4). 

Kunugj H, Fukuda R, Hattori M, Kato T, Tatsumi M, Sakai T, Hirose T, Ntuiko S. C677T polymorphism in methylenetetrahydrofolate reductase gene and psychoses. Mol Psychiatr 1998 3 435-437. 

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