[P3-65] Genetic Analysis for Benign Familial Epilepsies of the First Two Years of Life in a Chinese Cohort
[Purpose] To explore genetic background involved in Chinese families with benign familial epilepsies of the first two years of life which including benign familial neonatal epilepsy (BFNE), benign familial neonatal-infantile epilepsy (BFNIE) and benign familial infantile epilepsy (BFIE). [Methods] We collected families with BFNE, BFNIE and BFIE, and used PCR-DNA sequencing and targeted next-generation sequencing to detect mutation in those families. [Results] A total of 81 families were collected, including 4 BFNE, 8 BFNIE, and 69 BFIE. Genetic testing led to the identification of gene mutations in 57 families (57/81, 70.4%), including 40 families with PRRT2 mutations, 8 with KCNQ2 mutations, 8 with SCN2A mutations, and one with GABRA6 mutation. In BFNE, mutations specifically involved KCNQ2 (3 of 4 families). In BFNIE, mutations were found in 7 of 8 families, including 3 families with KCNQ2 mutations, 3 with SCN2A mutations, and one with PRRT2 mutation. In BFIE, gene mutations were found in 47 of 69 families (68.1%), including 2 families with KCNQ2 mutations, 5 with SCN2A mutations, 39 with PRRT2 mutations, and one with GABRA6 mutation. [Conclusions] The molecular cause was identified in about 70% families in our cohort. KCNQ2 is the only gene related to BFNE in our cohort. Both KCNQ2 and SCN2A have an important role in BFNIE, and can also be involved in families with a delayed age of onset. The mutations of PRRT2 is main responsible for BFIE in the Chinese population. The GABRA6 mutations might also be involved in BFIE.