[Gene diagnosis of lysosomal diseases]

Molecular genetic analysis of lysosomal storage diseases has revealed numerous mutant genes for each disease, and the results have been applied to gene diagnosis in patients and their family members. In general, the same mutant gene is not always found in different families. Confirmation of a mutant gene is necessary for each proband case in a family, although some common mutations can be screened for patients in a specific ethnic population, such as 151T mutation of the beta-galactosidase gene among Japanese cases of adult GM1-gangliosidosis. The result of gene analysis is generally clear and provides a solid diagnosis for each member at risk in a family. Gene analysis and conventional enzyme assays should be performed in a mutually complementary manner for laboratory diagnosis of lysosomal diseases.