MTHFR stands for methylenetetrahydrofolate reductase, MTHFR C667T polymorphism is associated with various diseases such as, vascular, cancer, neurology, diabetes and psoriasis. The MTHFR enzyme is important for folic acid metabolism which is an integral process for cell metabolism in DNA, RNA and protein methylation. The mutation of the MTHR gene causing the C677T polymorphism is located at exon 4, resulting in the conversion of valine to alanine at codon 222, a common polymorphism that reduces the activity of this enzyme. Persons with this mutation have a higher homocysteine level, a lower folic acid concentration and a low amount of vitamins. Hyperhomocysteine is an emerging risk factor for several cardiovascular diseases. The expression of the increased hyperhomocysteine can be detected with this PCR kit, also an analysis can be done for the mutation on gene 677. Symptoms that MTHFR C667T can cause are depression, bipolar disorder, colon cancer, acute leukemia, chronic pain and fatigue, nerve pain and migraines.