The article is devoted to the study of the frequency of polymorphic variants of genes GSTT1 and GSTM1 in patients with various forms of PMS. <...> Diagnosis of PMS was set by presence of cyclical manifestations of the disease in luteal phase of menstrual cycle on the basis of history-taking and results of patient’s self-observation diary for 2-3 menstrual cycles (R. Moos’ Menstrual Distress Questionnaire). <...> Molecular genetic analysis was performed in 50 women with premenstrual syndrome and in 25 women of control group. <...> So, results of the research indicate that the frequency of non-functional allele of glutathione S-transferase genes M1 and T1 (GSTT1, GSTM1) in women with PMS is not diff erent from that of women in the control group. <...> However, individuals with GSTT1 gene deletion polymorphism have tendency to development of severe form of PMS (OR=4.13, 95% CI=0.97-17.70, p=0.057). <...> This requires further researches in this direction in a large sample. <...> Оригинальные исследования INTRODUCTION Premenstrual syndrome (PMS) is one of the most spread neuroendocrine pathologies in gynecological practice. <...> It aff ects mostly women of reproductive age who suff er from numerous physical and psychological symptoms which appear in luteal phase of menstrual cycle [1]. <...> Glutathione-S-transferases (GST) are the large group of enzymes of diff erent classes that are directly involved in the second phase of biotransformation of foreign substances. <...> Diff erent ability to metabolize xenobiotics is provided by diff erences in the composition of isoenzymes. <...> Genes GSTM1 and GSTT1 were not studied enough in development of gynecological diseases. <...> We found research about their role in pathogenesis of polycystic ovarian syndrome. <...> Risk of polycystic ovarian syndrome in women with genotype GSTM1 0/0 increases in 3.7 times, and by combined deletions of genes GSTM1 and GSTT1 – in 34.5 times [9]. <...> Deletion of GSTM1 is associated with development of adenomyosis and leiomyoma [11]. <...> The aim of this study was to investigate the frequency of polymorphic variants of genes GSTT1 and GSTM1 in patients with various forms of PMS. <...> MATERIAL AND METHODS The study included 200 women with premenstrual syndrome, which formed basic group. <...> The control group consisted of 50 healthy women without diagnosis of PMS. <...> Diagnosis of PMS was set by presence of cyclical manifestations <...>