Mutation screening of the glucocerebrosidase gene by SSCP analysis revealed an 
abnormal pattern of exon 10 in two unrelated Italian Gaucher patients. Direct 
sequencing of the mutated samples identified a G6490-->A transition. The same 
mutation has been described before in a Japanese patient with Gaucher disease 
type III. The clinical phenotype of our patients was type I in one whose second 
allele carried the N370S mutation and type II in the other one with a L444P 
mutation. In this latter the G6490-->A substitution cancels a normal Msp I site, 
while on the opposite chromosome the T6433-->C mutation (L444P) introduces a new 
Msp I site. Thus, digestion with Msp I of the amplified exon 10 is a useful 
method for identifying the two mutations simultaneously.