ATP7B analysis of a Wilson disease family

Wilson disease is a genetic copper toxicosis due to hepatic copper transporter ATP7B deficiency. The primary lesion is copper-induced liver damage that progresses to cirrhosis, and may be complicated by extrahepatic lesions. Compound heterozygous mutations were identified in the ATP7B of a 16-year-old male patient with neurological Wilson disease. A family study disclosed different mutations in the parents, compound heterozygous mutations from the parents in the 12-year-old sister, and a maternal mutation in the 14-year-old sister. According to the autosomal recessive inheritance of this disease, the family members with compound heterozygous mutations are affected, but those with a heterozygous mutation are not affected by copper toxicosis. Both the proband and an asymptomatic sister with the disease trait were effectively treated with penicillamine and vitamin B₆. ATP7B analysis, recently authorized in Japan, provides a noninvasive, definitive diagnosis of Wilson disease.