SCN1A Gene Variation in Epilepsy and Migraine Patients

Mutation of sodium voltage-gated channel alpha subunit 1 (SCN1A) gene is an important cause of genetic epilepsy and familial hemiplegic migraine. However, data related genetic variation of SCN1A in Indonesia is limited. This study aimed to identify SCN1A gene variation in idiopathic epilepsy and common migraine patients in Aceh province, Indonesia. A case-control study was conducted at Dr. Zainoel Abidin Hospital, Banda Aceh, Indonesia from  March 1 st to August 30 th 2015. Gene variation analysis of exon 26 of SCN1A gene was conducted in 33 patients with idiopathic epilepsy, 33 with common migraine and 30 controls using polymerase chain reaction (PCR) and direct sequencing. DNA extraction was carried out at the School of Medicine, Syiah Kuala University, Banda Aceh, Indonesia. Amplification and sequencing of exon 26 of the SCN1A gene were conducted at the Faculty of Medicine, Gadjah Mada University, Yogyakarta, Indonesia and 1st BASE Pte. Ltd. Laboratory, Singapore, respectively. SCN1A gene variations were identified in two partial secondary generalized epilepsy patients. In one patient, four silent mutations at nucleotide position A4440T (Leu1480Leu), T4443C (Leu1481Leu), A5046G (Leu1682Leu) and C5121T (Asp1707Asp) were identified. One silent mutation at position G5505A (Glu1835Glu) was found in another patient. There was no gene variation identified among controls and common migraine patients. Five genetic variations in exon 26 of SCN1A were identified in two patients with partial secondary generalized epilepsy in Aceh, Indonesia. The association between these variants and epilepsy need to be clarified.