RESUMO
BACKGROUND AND PURPOSE: The aim of our study was to evaluate the frequency of the C677T variant in the methylenetetrahydrofolate reductase (MTHFR) gene in patients with migraine with or without aura and to find an association between this variant and vascular lesions in magnetic resonance imaging of the head, presence of patent foramen ovale (PFO) and increased level of homocysteine. MATERIAL AND METHODS: Ninety-one patients with migraine, aged 19-57, were investigated in this study. The MTHFR C677T variant was genotyped in this group and levels of homocysteine, folic acid and vitamin B12 were measured. Transcranial Doppler sonography with test for PFO detection by injection of air contrast during the Valsalva manoeuvre was performed in each patient. RESULTS: Frequency of the C677T variant in the MTHFR gene was similar in patients and controls. Hyperhomocysteinaemia was significantly more frequent in migraine patients with the C677T variant. The prevalence of PFO was significantly higher in migraine patients with aura and the homozygous variant of the MTHFR gene. CONCLUSIONS: Frequency of the C677T variant in the MTHFR gene was similar in patients and controls. Significantly more frequent prevalence of PFO in migraine patients with aura (with homozygous recessive genotype of MTHFR probably suggests their common genetic basis. Hyperhomocysteinaemia was significantly more frequent in migraine patients with the C677T variant, which could be an additional risk factor of this disease.