Early-onset autosomal-recessive parkinsonian-pyramidal syndrome

Genetic factors have been known to contribute to familial Parkinson's disease (PD), one of the most common neurodegenerative disorders. During the past decade, six of eleven causative genes linked to familial forms of PD have been identified to associate with autosomal-recessive young-onset Levodopa-responsive parkinsonism. Among these genes, mutations in Parkin, PINKl and DJ-1 are associated with a relatively typical parkinsonian phenotype with sustained treatment response to Levodopa. However, mutations inATP13A2, PLA2G6 and FBX07 are often associated with rapidly progressive parkinsonism and with additional features including pyramidal signs, cognitive decline and loss of sustained Levodopa responsiveness.Clarifying the phenotypes of each of these autosomal-recessive parkinsonian-pyramidal syndromes and understanding the mechanism ot these causative gene products might illuminate the pathogenesis of dopaminergic neuronal degeneration also in the common forms of PD.