title: A novelPOLGgene mutation in a patient with SANDO.
abstract: The human mitochondrial genome is replicated by DNA polymerase γ, which is encoded by polymerase γ gene (POLG1) on chromosome 15q25. Patients withPOLG1mutations usually present as Alpers' syndrome or progressive external ophthalmoplegia. Our patient was a 48-year old woman with sensory ataxic neuropathy, dysarthria, ophthalmoplegia, and dysphagia. Sequence analysis revealed that she has two heterozygous missense mutations in thePOLG1, a c.1774C>T substitution in exon 10, which results in a p.L591F amino acid change; and a c.3286C>T substitution in exon 21, which results in a p.R1096C amino acid change. The 1774C>T substitution is a novel mutation. Previously described adult patients with one mutation in exon 10 and the other in exon 21 ofPOLG1had presented with progressive external ophthalmoplegia. We now describe a patient with mutations in the same exons but suffering from the more complex clinical syndrome of sensory ataxic neuropathy, dysarthria, ophthalmoplegia.
authors.affiliation: Department of Neurology, Columbia University Medical Center, New York, NY.
authors.forename: Bulent
authors.initials: B
authors.lastname: Kurt
authors.forename: Ali B
authors.initials: AB
authors.lastname: Naini
authors.forename: William C
authors.initials: WC
authors.lastname: Copeland
authors.forename: Jiesheng
authors.initials: J
authors.lastname: Lu
authors.forename: Salvatore
authors.initials: S
authors.lastname: Dimauro
authors.forename: Michio
authors.initials: M
authors.lastname: Hirano
keywords: Novel mutation; PEO; POLG1; SANDO