Mitochondrial DNA mutations in Japanese patients with optic neuropathy unassociated with a mutation at nucleotide position 11,778

We examined for mitochondrial DNA (mtDNA) mutations at nucleotide positions (nt) 3460, 14,484, 9438, 9804, and 15,257 in ten Japanese patients with idi opathic optic neuropathy unassociated with a mutation at nt11,778. The mtDN As were amplified by polymerase chain reaction (PCR), the products were dig ested with restriction enzymes, and the sizes of the fragments were analyze d on 8% polyacrylamide gel. Of the ten patients, one had an mtDNA mutation at nt3460 and another patient had a mutation at nt14,484. We suggest that m tDNA mutations in Japanese patients with optic neuropathy unassociated with a mutation at nt11,778 should be further investigated.