Polymorphism of the locus CHE1 of pseudocholinesterase in Italy.

: A sample of the Italian population was investigated to determine the CHE1*u, CHE1*a and CHE1*f allelic variants at the polymorphic locus CHE1 for the serum cholinesterase enzyme. We examined 4051 serum samples from schoolchildren of Milan and estimated the following allelic frequencies for the CHE1 locus: CHE1*u = 0.9636; CHE1*a = 0.0263; CHE1*f = 0.0101. These allelic frequencies are compared with those from other Italian, European, North African and Middle-Eastern countries. Our study confirms the validity of Garry's method in discriminating between the "usual" genotype and the "atypical" and "fluoride-resistant" ones.