Menkes' kinky hair syndrome: a genetic disease involving copper.

The kinky hair syndrome (KHS) is an X-linked defect of copper transport in man. An animal model is available in mutants at the X-linked mottled locus in mice. The defect does not involve the uptake of copper from the intestinal lumen but rather the transport of copper from intestinal cells. The reduced activity of several copper-dependent enzymes and the lower copper content of serum, liver, and probably brain account for the manifestations of the disorder which are evident at, or shortly after, birth. Intrauterine involvement is likely but prenatal diagnosis is not yet possible. Although the delivery of iron to the erythropoietic system, and its utilization, are impaired in nutritionally induced copper deficiency, as is neutrophil production, these processes appear normal in KHS. thus, adequate copper to carry them out is available in KHS. While there may be more than one transport system for copper (only one of which is affected in KHS) it is also possible that the hematopoietic tissue in KHS, like the intestinal cells, has abnormally high afficity for copper. The presence of multiple alleles at the KHS locus (and at other genetic loci) in man, which cause different degrees of reduction in copper transport, could account for variations in the susceptibility to copper deficiency observed in infant populations.