IS IT ALL IN THE GENES?

▸ Nicastro E, Loudianos G, Zancan L, . Genotype–phenotype correlation in Italian children with Wilson’s disease. J Hepatol 2009;50:555–61.

Wilson disease is an autosomal recessive condition with >400 mutations described in the gene that encodes a transmembrane copper-transporting P-type ATPase. The disease presents with a broad range of manifestations, and age of onset ranges from 2 to 71 years. However, the variability in the clinical and laboratory features has not been explained.

Nicastro et al retrospectively studied 58 children (34 male, median age at diagnosis 7.4 years) from 47 unrelated families using a two-step approach (using single-strand conformation polymorphism (SSCP) and sequencing). This revealed 34 different mutations accounting for 91% of the studied alleles. Mutations were grouped as homozygotes and compound heterozygotes for missense mutation versus homozygotes for nonsense and frameshift mutations. Serum ceruloplasmin and copper were lower among subjects homozygous for nonsense and frameshift mutations than for those with missense mutations. After therapy, serum alanine aminotransferase did not normalise in 23.6% of patients with missense mutations vs 45.5% of patients with nonsense/frameshift mutations. This differentiation …