TYPE-1 GAUCHER DISEASE - MOLECULAR, BIOCHEMICAL, AND CLINICAL CHARACTERIZATION OF PATIENTS FROM NORTHERN PORTUGAL

We report the study of 16 catholic type 1 Gaucher disease patients originating from a well-defined region in the north of Portugal where a relatively high incidence is observed. The patients were screened for mutations: 3060G → A, 5841A → G, 5976C → G, and 6433T → G, which enabled the identification of 27 of the 32 mutated alleles. Four different genotypes were identified, namely 5841G/6433C (n = 6). 5841G/5841G (n = 5), 5841G/? (n = 4). and 6433C/? (n = 1). All but one of the patients carried at least one 5841G mutated allele, making its frequency 62.5%, which is similar to that described for Ashkenazi Jewish patients. The 5841G homozygotes presented an overall milder clinical profile, whereas no clear genotype/phenotype correlation could he established for heterozygous patients. On the basis of residual glucocerebrosidase activity, no distinction could be made between 5841G homozygotes and 5841G/6433C compound heterozygotes. Patients that had at least one 5841G allele (encoding the Ser 370 mutated enzyme) all presented a cell-type-specific residual glucocerebrosidase activity as well as an increased molecular activity when measured in the presence of the physiological activators. © 1993 Academic Press. All rights reserved.