Summary
This syndrome is characterised by adult-onset severe sensory ataxic neuropathy, dysarthria and chronic progressive external ophthalmoplegia. The prevalence is unknown. Other common features include progressive gait unsteadiness, absent deep tendon reflexes, the presence of Romberg's sign, a decreased sense of vibration and proprioception and detection of red ragged fibres on muscle biopsy. The syndrome is associated with mitochondrial DNA mutations in either the POLG1 or TWINKLE genes. Autosomal recessive and dominant inheritance, as well as sporadic occurrence, have been suggested.
Last update: June 2007