July 1, 1999
Diagnosis and Symptoms
Question from Bethesda, Maryland, USA:
Does mitochondrial diabetes present only in youngsters? Is there ever a motor “myoclonic” neurological association with any of its genetic forms?
One of the syndromes of mitochondrial diabetes is MERRF or Myoclonic Epilepsy with Ragged Red Fibres. In a paper by Austin SA. et al in Neurology 51:1447,1998, diabetes is also described in a group of families with this condition.
As with all maternally derived mitochondrial disorders, the phenotype is quite variable on account of heteroplasmy and one would expect this to affect the age of onset, though I could not find specific figures on this point.