Many publications demonstrate a relationship between acute myocardial infarction and genetic mutations. In our case, a 26-yearold young woman was admitted to the hospital with complaints of severe chest pain. She had no risk factors for coronary heart disease but two of her sisters and one of her brothers had suffered sudden cardiac death. DNA samples obtained from peripheral blood were studied by polymerase chain reaction (PCR) and showed mutations in methylenetetrahydrofolate reductase (MTHFR) gene region C677T and heterozygous mutation in prothrombin gene region G20210A.