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Mitochondrial DNA (mtDNA) A 3243G mutation associated with an annular perimacular retinal atrophy

E Adjadj1, K Mansouri, F-X Borruat

  • 1Hôpital Ophtalmique Jules Gonin, Lausanne, Switzerland.

Klinische Monatsblatter Fur Augenheilkunde
|May 6, 2008
PubMed
Abstract

Insights

Mitochondrial DNA (mtDNA) 3243 mutation can cause maculopathy, a retinal condition. Early examination for this eye disease is recommended for patients with mtDNA mutations, even if asymptomatic, to detect potential vision loss.

Area of Science:

  • Ophthalmology
  • Genetics
  • Mitochondrial Diseases

Background:

  • A specific point mutation in mitochondrial DNA (mtDNA) at locus 3243 is linked to various syndromes like MIDD and MELAS.
  • These mutations can also manifest as cardiac, digestive, endocrine, or exocrine dysfunctions.
  • This study investigates a unique maculopathy associated with the mtDNA 3243 mutation.

Observation:

  • Two patients with the mtDNA 3243 mutation were studied.
  • One patient was asymptomatic with 10/10 visual acuity, while the other experienced visual loss with 6/10 and 0.5/10 acuity.
  • Both patients presented with chorioretinal areolar atrophy, a form of geographic maculopathy.

Findings:

  • The study observed a perimacular annular retinal atrophy in both patients.
  • Case 1 showed slow progression of maculopathy over 15 years, with moderate visual acuity loss and significant handicap from annular scotoma.
  • The findings highlight a distinct ocular manifestation in patients with this mtDNA mutation.

Implications:

  • Patients with mtDNA 3243 mutations should undergo regular eye examinations for maculopathy, regardless of symptoms.
  • The presence of geographic maculopathy, particularly with diabetes mellitus and/or deafness, should prompt consideration of the mtDNA 3243 mutation.
  • This research underscores the importance of ophthalmological screening in the comprehensive management of mitochondrial DNA-related disorders.

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