Mitochondrial tRNA(Cys) mutation A5823G in a patient with motor neuron disease and temporal lobe epilepsy

We discovered a new homoplasmic mutation in the mitochondrial cysteine tRNA of a 60-year-old Caucasian male suffering from asymmetrical pure lower mot or neuron disease (MND) and temporal robe epilepsy (TLE). Furthermore, titr ations with Amytal, an inhibitor of NADH:CoQ oxidoreductase, revealed mild mitochondrial dysfunction in skeletal muscle tissue, which was described in patients with MND in an earlier report. The mutation was undetectable in 1 55 Caucasian controls of both sexes, in 40 MND patients and in 13 individua ls suffering from TLE. It was, however, detected in a heteroplasmic state i n the patient's mother, who did not suffer from a neurological disorder. Si nce this rare mutation affected a nonconserved base position and was not ob served in MND or TLE materials, its relation to disease remains unclear. Co pyright (C) 2000 S. Karger AG, Basel.