[PS4-1D-1] Whole Exome Sequencing in Intractable Pediatrics Epileptic Patients: King Chulalongkorn Memorial Hospital Experiences
Whole exome sequencing (WES) were performed in 36 intractable pediatrics epilepsy patients (19 Males, 17 female) at King Chulalongkorn Memorial Hospital from January 2015- August 2016. Twenty-three exome results (63.9%, 10 males, 13 females) revealed mutations in epilepsy related genes. The results were negative in 13 patients (36.1%, 9 males, 4 females) The most common mutations are sodium channels muattions (9, 25 %, including SCN1A (5, 13.9%), SCN2A (2, 5.6%), SCN8A (2, 5.6%). There are two cases each of pyridoxal-5-phosphate responsive epilepsy, (PNPO, 2 , 5.6 %), two unrelated cases of congenital hypotonia-seizure due to PIGA mutation (2 , 5.6%) and a pair of siblings with progressive-photosensitive-myoclonic epilepsy due to FARS2 mutation (2 patients, 5.6%). Six more patients (17 %) were identified with different epilepsy related mutations (ALDH7A1, PCDH19, KCNA2, KCNMA1, SLC1A2, GABRA1 and RELN). Among these patients, one pyridoxine dependent epilepsy, all pyridoxal-5-phosphate responsive epilepsies and two of the five SCN1A were diagnosed clinically (5, 13.9 %) and exome results provide confident to adjust, reduce or discontinue anticonvulsants. In the last eighteen patients (50 %), exome results introduce new diagnosis, resulting in a better seizure control in patients with SCNA1, SCNA2 and myoclonic epilepsies ( KCNA2 and FARS2). Among thirteen patients with no identifiable mutation, three patients have early infantile epileptic encephalopathies, three patients with myoclonic epilepsies, two patients had autism with epilepsies, four patients had status epilepticus at various ages and one with clinical nocturnal frontal lobe epilepsy.