RRM2B mutations are frequent in familial PEO with multiple mtDNA deletions

This is the authors' abstract. We don't add key points for this paper.

Disorders of mitochondrial DNA (mtDNA) maintenance leading to multiple mtDNA deletions are a significant cause of inherited neurologic disease in adults, but the underlying nuclear gene defects remain elusive in many patients. Following the recent description of a truncating mutation in the RRM2B gene-encoding the small subunit, p53R2, of the p53-inducible ribonucleotide reductase protein-in 2 families with autosomal-dominant progressive external ophthalmoplegia (adPEO), 1 we determined the frequency of RRM2B mutations in a large cohort of patients with PEO and multiple mtDNA deletions in muscle in whom mutations in all known candidate genes (e.g., POLG, POLG2, SLC25A4, and PEO1) had been excluded. 2