Mutations in the mitochondrial DNA gamma polymerase (POLG) may cause Alpers syndrome, mitochondrial DNA depletion, and non-syndromic status epilepticus: implications for valproate therapy. - Poulton J; Jayawant S; O'Rourke A; Morten K; Ashley N; Narasimhan M; Fratter C (Developmental Medicine & Child Neurology, 2007)