Definitive diagnosis can be made in males by testing for deficient α-galactosidase A (α-GAL) enzyme activity in plasma, leukocytes, cultured skin fibroblasts, biopsied tissue, or dried blood, while diagnosis in females often requires DNA analysis.1
Because females with Fabry disease can have α-GAL activity in the low to normal range, the patient should receive DNA analysis (either mutation analysis or linkage analysis, depending on whether the family mutation is known).1 Though an enzyme assay is not required for diagnosis, results can be helpful for understanding genotype-phenotype correlations.