Genetic factors that increase susceptibility to oxidative stress, endothelial disfunction and, possibly, stroke include angiotensin-converting enzyme gene deletion polymorphism (ACE-DD) and the methylentetrahydropholate reductase (MTHFR) C677-TT polymorphism. The relationship of ACE-DD genotype to ischemic stroke and cardiovascular disease is controversial, but it has been independently linked to lacunar infarction, in the absence of carotid atheroma. Lea et al. (2005) reported that the ACE DD genotype acts in combination with the MTHFR T/T genotype to increase migraine susceptibility, with the greatest effect in those with aura. The "TT" polymorphism is also associated with an increased risk of migraine with aura, independent of other cardiovascular risk factors. The aim of our study was to evaluate the incidence of ACE and MTHFR genes polymorphisms in a consecutive series of migrainous patients and of patients affected by myocardial infarction. We studied a series of 103 migrainous patients (1), whose age was between 13 and 75 years (81 suffering from migraine without aura, MwA, 9 from migraine with aura, MWA, 13 from mixed forms MwA-MWA, according to ICHD-II 2004 criteria) and of 336 patients (2) suffering from ischaemic cardiopathy (myocardial infarction, MI). The analysis, based on Polymerase Chain Reaction (PCR) and on reverse-hybridization, showed as follows: MTHFR (C677T): 60 patients (58%) (1) and 186 (56%) (2) were heterozygous; 9 patients (9%) (1) and 54 (16%) (2) were mutated. The result of 1 patient (2) was unknown. MTHFR (A1298C): 54 patients (52%) (1) and 146 (44%) (2) were heterozygous, 7 patients (7%) (1) and 33 (10%) (2) were mutated. The result of 1 patient (2) was unknown. ACE (evaluated on 101 patients (1) and 245 (2)): 45 patients (43%) (1) and 133 (54%) (2) had an ID genotype; 42 (41%) (1) and 87 (36%) (2) had a DD genotype. The results of our study confirm the high incidence in the genetic polymorphisms ACE and MTHFR in migraineuse. These data are confirmed in the sample of patients affected by myocardial infarction. This gives evidence of a strong relationship between migraine and major vascular diseases and let us hypothesize an important role of ACE and MTHFR system in the pathogenetic model of migraine for its capability to interfere with the endothelial regulation tone. Once an effective role in the genesis of migraine and in the increased risk of migrainous patients to evolve into an ischemic pathology has been obviously assigned to this genetic mutation, future researches must aim through wider and more controlled casistics also to clarify the role that drugs acting on these systems may have on the resolution of these diseases.