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Retinal dystrophy associated with a single-base deletion mutation in mitochondrial DNA 3271 in patient with MELAS

Kenji Ozawa1, Kiyofumi Mochizuki2, Yusuke Manabe2

  • 1Department of Ophthalmology, Gifu University Graduate School of Medicine, 1-1 Yanagido, Gifu, 501-1194, Japan. kj-ozawa@umin.ac.jp.

Documenta Ophthalmologica. Advances in Ophthalmology
|February 1, 2019
PubMed
Abstract

Insights

This study details a rare case of MELAS with the m.3271delT mitochondrial DNA mutation, revealing significant retinal pigment epithelium atrophy and severe rod dysfunction. These findings highlight distinct retinal alterations in this rare MELAS variant.

Area of Science:

  • Ophthalmology
  • Neurogenetics
  • Mitochondrial Diseases

Background:

  • Mitochondrial encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) is a mitochondrial DNA disorder.
  • The common mutation is m.3243A>G; however, rare mutations like m.3271delT also cause MELAS.

Observation:

  • A 37-year-old woman with nyctalopia presented with MELAS and the m.3271delT mutation.
  • Ophthalmological examinations included SD-OCT and electroretinography (ERG).

Findings:

  • Retinal examination revealed RPE atrophy and reduced interdigitation zone on SD-OCT.
  • Full-field and multifocal ERGs showed severe rod and cone dysfunction, with prolonged implicit times.

Implications:

  • The m.3271delT MELAS mutation causes wider RPE atrophy and more severe rod dysfunction than the common m.3243A>G mutation.
  • This case expands the understanding of MELAS phenotypic variability and its ocular manifestations.
Keywords:
3271M.3271delTMELASMitochondrial DNARetinopathy

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