Wilson's disease is an autosomal recessive disorder of hepatic copper metabolism caused by mutations in a gene encoding a copper-transporting P-type ATPase. We report the clinical and molecular characterization of six members from three unrelated Colombian kindred. Completed sequence DNA analysis linked to the gene ATP-7B from patient wd-1 revealed a novel A to C transversion in exon 17 at position 3856 (A3856C) of the ATP-7B mRNA resulting in a threonine for proline substitution at position 1232 of the ATP-7B protein (T1232P). Additionally, two novel polymorphisms were detected (2785G:Gly875 in exon 11; and intron at +38 a > c:tgcgcccga in exon 19). All affected individuals were homozygous for the T1232P mutation and displayed neurologic and neuropsychiatric dominant onset. This work expands the knowledge about the number, type, and implication of mutations in WD.