ATP7B

About ATP7B

ATP7B on chromosome 13q14.3 encodes a copper transporting P type ATPase expressed mainly in liver cells, where it delivers copper to ceruloplasmin and moves excess copper into bile for excretion. Variants on both copies cause Wilson disease, an autosomal recessive copper overload disorder classically estimated to affect about 1 in 30,000 people. Copper first accumulates in the liver, causing hepatitis, cirrhosis, or sudden liver failure, and then in the brain, particularly the basal ganglia, causing tremor, dystonia, parkinsonism, difficulty with speech and swallowing, and psychiatric symptoms. Copper deposited in Descemet membrane of the cornea forms the Kayser Fleischer rings visible on eye examination. More than 500 variants have been described, and H1069Q is the most common in Europe. Diagnosis combines clinical findings, low ceruloplasmin, increased urinary copper, raised liver copper, and genetic testing. The disease was described by the British neurologist Samuel Alexander Kinnier Wilson in 1912, and the gene was identified in 1993. Treatment with copper chelating agents such as penicillamine and trientine, and zinc, which blocks intestinal copper absorption, can prevent or reverse many manifestations, making Wilson disease one of the few treatable genetic causes of liver disease and movement disorders. Acute liver failure may require liver transplantation.