Parra OI, Estrada GRA, Guzmán GMO

Language: Spanish
References: 16
Page: 15-18
PDF size: 135.90 Kb.

ABSTRACT

Background: The hyperhomocystinemia has been considered an independent risk factor for atherosclerosis and atherotrombosis. The individuals with the 677 C›T mutation in the gene for 5,10 methyltetrahydrofolate reductase (677 MTHFR) are at highest risk.
Objective: To determine the relationship between 677 mutation MTHFR and the increased plasmatic homocysteine levels.
Patients and methods: 70 Mexican patients with a thrombophilia state were classified in three groups: 1) homozygote (11) 677 mutation MTHFR, 2) heterozygote 677 mutation MTHFR (33) and 3) normal homozygote (26). The homocysteine plasmatic levels were calculated and then, we searched the relation of the genotypes with the plasmatic homocysteine levels.
Results: We only found two (2.85%) patients with high homocysteine plasmatic levels, one with 45.73 µmol/L and heterozygote genotype, and other with 25.9 µmol/L and homozygote genotype. The median plasmatic homocysteine levels in the three groups were: homozygote mutation 10.33 µmol/L; heterozygote mutation 10.15 µmol/L and 9.3 for the normal homozygote. There was not a statistically significative difference among the genotypes and the homocysteine plasmatic levels.
Conclusions: In this study it has been demonstrated that 677 mutation MTHFR was not associated with high plasmatic homocysteine levels in Mexican patients. The mechanism implied can be caused by other defects in the different proteins present in the homocysteine metabolism.

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