Yalçin Ozlem, Cağlayan S Hande, Saltik Sema, Cokar Ozlem, Ağan Kadriye, Dervent Aysin, Steinlein Ortrud K
Department of Molecular Biology and Genetics, Boğaziçi University, Istanbul, Turkey.
Turk J Pediatr. 2007 Oct-Dec;49(4):385-9.
Benign familial neonatal convulsions (BFNC) is a rare monogenic subtype of idiopathic epilepsy exhibiting autosomal dominant mode of inheritance. The disease is caused by mutations in the two homologous genes KCNQ2 and KCNQ3 that encode the subunits of the voltage-gated potassium channel. Most KCNQ2 mutations are found in the pore region and the cytoplasmic C domain. These mutations are either deletions/insertions that result in frameshift or truncation of the protein product, splice-site variants or missense mutations. This study reveals a novel missense mutation (N258S) in the KCNQ2 gene between the S5 domain and the pore of the potassium channel in two BFNC patients in a Turkish family. The absence of the mutation both in the healthy members of the family and in a control group, and the lack of any other change in the KCNQ2 gene of the patients indicate that N258S substitution is a pathogenic mutation leading to epileptic seizures in this family.
良性家族性新生儿惊厥（BFNC）是特发性癫痫的一种罕见单基因亚型，呈常染色体显性遗传模式。该疾病由编码电压门控钾通道亚基的两个同源基因KCNQ2和KCNQ3的突变引起。大多数KCNQ2突变位于孔区和细胞质C结构域。这些突变包括导致蛋白质产物移码或截短的缺失/插入、剪接位点变异或错义突变。本研究在一个土耳其家庭的两名BFNC患者中发现了钾通道S5结构域与孔之间的KCNQ2基因中的一个新的错义突变（N258S）。该家族健康成员及对照组中均无此突变，且患者KCNQ2基因无任何其他变化，这表明N258S替换是导致该家族癫痫发作的致病突变。
