WWOX-associated encephalopathies: identification of the phenotypic spectrum and the resulting genotype-phenotype correlation.

Epileptic encephalopathies are a group of disorders in which epileptiform abnormalities cause progressive deterioration in cerebral function. Genetic causes have been described in several of the epileptic encephalopathies, and many previously unknown genes have been identified. WW domain-containing oxidoreductase (WWOX) has recently been implicated in autosomal recessive spinocerebellar ataxia type 12 (SCAR12) and severe early-onset epileptic encephalopathy. With whole-exome sequencing, we identified a homozygous WWOX missense mutation, p.Leu239Arg, in a girl from a consanguineous family with psychomotor developmental delay, acquired microcephaly, and epileptic seizures. WWOX-related epileptic encephalopathy is a rare condition but it should be considered in cases having early epileptic spasms and parental consanguinity.