A patient with Wilson's disease is described who presented with dystonic tr
emor in a family with an apparent dominant history of tremor. Subsequent in
vestigation showed that the patient's mother had essential tremor, with mol
ecular analysis of the ATP7B gene excluding the possibility of pseudodomina
nt inheritance. This case highlights the importance of considering the poss
ibility of Wilson's disease in every young patient with a movement disorder
, even where the clinical picture does not suggest a recessively inherited
disorder.