Role of metallothioneins in copper transport in patients with Menkes syndrome.

Fibroblasts from infants with Menkes kinky hair syndrome, which accumulate excessive quantities of copper, are thought to represent a disorder of copper storage or transport. Because of this abnormality, it was thought that they might provide a useful system for investigation of the presumed storage or transport protein metallothionein. Data are presented which are consistent with defective copper efflux from the mutant cells. Because of the more specific role of metallothionein in cadmium detoxification, studies of cadmium metabolism were undertaken which demonstrated abnormal cadmium retention and metallothionein induction in the mutant cells. The association, therefore, of a defect of cadmium metabolism and storage with an abnormality of copper efflux provides evidence implicating metallothionein in copper transport for fibroblasts.