Retrospective evaluation of the effects of SCN9A and SCN10A gene polymorphisms on the development of chronicity in patients with chronic and episodic migraine

Migraine; is defined as polygenic primary headache with severe, throbbing character, unilateral, exacerbated and accompanied by systemic symptoms. Migraine; according to the frequency of attacks, it is divided into two subtypes as episodic and chronic migraine. It progresses from episodic form to chronic form and shows various characteristic features. If it is intervened in this process, the process of becoming chronic can be prevented. Therefore, elucidating the transition between the two types of migraine is of great importance in controlling the course of the disease. Voltage-gated sodium channels, one of these ion channels, are involved in the pathogenesis of migraine by causing cortical spreading depression and altered sensitivity to dural afferents. Nav1.7 and Nav1.8, which are voltage-gated sodium channels, play a role in increasing nociceptor sensitivity and chronic pain. In the literature, it has been shown that polymorphisms in the SCN9A and SCN10A genes encoding these channels are also effective in chronic pain and in the change of pain sensitivity. In the current thesis; The effects of SCN9A rs7595255, rs12622743, rs11898284 and SCN10A rs6795970, rs6801957 SNPs, which are known to be associated with pain sensitivity, in the diagnosis of episodic/chronic migraine and migraine chronification were investigated. For this purpose, 227 migraine patients, who applied to Bursa Uludağ University Faculty of Medicine Neurology Department between 2014 and 2015, were included in the study and these patients were included in the ICHD-3 classification. According to the study, 151 were episodic and 76 were chronic migraine. After an average of 96 months of follow-up, anamnesis information was obtained from the patients and related polymorphisms were evaluated with the clinical picture. Although there is no previous study on this subject in the literature, these SNPs were not found to be statistically significant in the diagnosis and chronification of episodic/chronic migraine. As a result, it is thought that different SCN9A and SCN10A polymorphisms should be evaluated in larger populations together with these polymorphisms in future studies, since this may be due to the variable ethnic origins, rate difference and sample size in the Turkish population. Keywords: SNP, SCN9A, SCN10A, Nav1.7, Nav1.8