HGPRT structural gene mutation in Lesch-Nyhan-syndrome as indicated by antigenic activity and reversion of the enzyme deficiency.

For three patients with the Lesch-Nyhan syndrome the existence of normal amounts of catalytically inactive hypoxanthine-guanine phosphoribosyltransferase (HGPRT) protein was demonstrated by using antibodies against the normal enzyme subunits. The lack of enzyme activity is reverted in virus transformed cells. Individual revertant cell clones contain different HGPRT enzymes as demonstrated here by isoelectric focusing. The data strongly support the idea of a structural gene mutation as the cause of enzyme deficiency in the Lesch-Nyhan syndrome.