Prenatal diagnosis of mitochondrial DNA8993 T----G disease

Am J Hum Genet. 1992 Mar;50(3):629-33.


We have previously described a family with a neurological syndrome comprising neurogenic muscle weakness, ataxia, retinitis pigmentosa, and variable sensory neuropathy, seizures, and mental retardation or dementia. This is associated with a heteroplasmic point mutation of mtDNA at bp 8993. The mother of a severely affected child underwent prenatal diagnosis in two further pregnancies. Analysis of chorionic villus samples showed a higher proportion of mutant mtDNA on both occasions, and this was reflected in the majority of fetal tissues, including brain and muscle. Prenatal diagnosis is a rational approach to the prevention of severe diseases caused by point mutations of mtDNA but is currently hampered by incomplete knowledge concerning the proportion of mutant mtDNA: its relationship to disease severity, how it may change during fetal and postnatal development, and its tissue distribution.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Child, Preschool
  • Chorionic Villi Sampling
  • DNA, Mitochondrial / genetics*
  • Female
  • Fetal Diseases / diagnosis*
  • Fetal Diseases / genetics
  • Humans
  • Intellectual Disability / diagnosis
  • Intellectual Disability / genetics
  • Mitochondria, Muscle / chemistry
  • Mothers
  • Mutation
  • Neuromuscular Diseases / diagnosis*
  • Neuromuscular Diseases / genetics*
  • Pregnancy
  • Prenatal Diagnosis*
  • Retinitis Pigmentosa / diagnosis
  • Retinitis Pigmentosa / genetics
  • Syndrome


  • DNA, Mitochondrial