Wilson's disease: an old disease keeps its old secrets

Wilson's disease is a rare condition characterized by a defect in biliary excretion of copper, due to a mutation of both alleles of "Wilson's disease" gene (ATP7b gene). Many different mutations have been identified in affected patients. Since the clinical presentation of the disease is highly heterogeneous, it has been suspected that this variability could be related to different phenotypes. In this paper, Folhoffer et al. report a series of 109 Hungarian patients with Wilson's disease. The authors identified 8 novel, previously unreported, mutations of ATP7b gene in their population. However, 17% of patients with an established diagnosis of Wilson's disease still did not have any identifiable mutation. Since not all exons were analyzed, more studies are needed to identify the corresponding mutations. Overall, the authors failed to document any genotype-phenotype correlation suggesting that non genetical factors are involved in the clinical variability of the disease.