A mitochondrial tRNA(Val) gene mutation (G1642A) in a patient with mitochondrial myopathy, lactic acidosis, and stroke-like episodes

Neurology. 1998 Jan;50(1):293-5. doi: 10.1212/wnl.50.1.293.


We studied a patient with the diagnosis of mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS) for mitochondrial DNA mutations in muscle. Established MELAS mutations were excluded. Mitochondrial DNA was further analyzed for mutations in the 22 tRNA genes by single-strand conformation polymorphism (SSCP) analysis; a tRNA(Val) mutation (G1642A) was found. The structure of the altered tRNA, the heteroplasmy, and the absence of the mutation in the mother and in 100 control subjects suggests that the tRNA(Val) mutation is associated with the MELAS syndrome.

Publication types

  • Case Reports
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Base Sequence
  • Child
  • Family Health
  • Humans
  • MELAS Syndrome / genetics*
  • Male
  • Mitochondria
  • Molecular Sequence Data
  • Nucleic Acid Conformation
  • Point Mutation*
  • Polymorphism, Single-Stranded Conformational
  • RNA / genetics*
  • RNA, Mitochondrial
  • RNA, Transfer, Val / chemistry
  • RNA, Transfer, Val / genetics*


  • RNA, Mitochondrial
  • RNA, Transfer, Val
  • RNA