Genetic diseases membrane-bound proteins

Severe alterations in copper metabolism occur in two genetic disorders, Wilson s disease and Menkes disease, both of these diseases arc rare and occur in about one in 100,000 birtKs. Both diseases involve naturally occurring mutations in copper transport proteins, i.e membrane-bound proteins that mediate the passage of copper ions through cell membranes. The copper transporters that are defective in these two diseases are not the same protein, but they are related. To express this relation in numbers, over half (57 a) of the sequence of amino adds, as they occur in the polypeptide chains, are identical. Both proteins are thought to utilize ATP to drive copper ions through membranes. 

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