[Molecular screening of the major mutations in the ARSA gene in patients with metachromatic leukodystrophy]. 
Metachromatic leukodystrophy (MLD) is an inherited storage disease caused by deficiency of arylsulfatase A (ARSA).  Molecular analysis of the major mutations in the ARSA gene was performed in 10 Ukrainian patients (from 9 families) with MLD.  According to the age of onset, late infantile MLD was identified in 3 patients, juvenile MLD in 5 patients, and adult MLD in 2 patients (sibs), respectively.  The ARSA activity in the patients was 2-26 nmol/h/mg protein (the normal activity has been established in our laboratory as 111.9 +/- 7.1 nmol/h/mg protein).  No correlation between enzyme activity and a clinical course of disease was revealed.  The IVS2 + 1 mutation was found at 2 of 20 alleles (in a patient with late infantile form) and the P426L mutation was found at 2 of 20 alleles (in two patients with juvenile form).  Thus, the total frequency of these two major mutations in the ARSA gene is 20% in Ukrainian MLD patients.