Mutation spectrum of α-Galactosidase gene in Japanese patients with Fabry disease.

The efficacy of pharmacological chaperone therapy for Fabry disease depends on the type of α-galactosidase A (GLA) mutations. Here, we examined the mutation spectrum of the GLA gene among patients from 115 Japanese families with Fabry disease. Of these, no pathogenic mutations were identified in six families (5.2%). In total, 73 different disease-causing mutations were identified: 41 missense (56.2%), 11 nonsense (15.1%), four in frame deletion (5.5%), 10 frameshift (13.7%), six splice site (8.2%), and one intronic (1.4%) mutations. The GLA mutations detected in later-onset phenotype patients with end-stage renal disease overlapped with those seen in classical patients, indicating that it is difficult to differentiate between these two phenotypes from gene mutations. Additionally, 33 families (28.7%) had amenable mutations to the pharmacological chaperone migalastat. In conclusion, our study is informative when considering genetic counseling and pharmacological chaperon therapy for Fabry disease.