Subtypes of Fabry disease and their presentation
Complete absence of, or less than 1% of normal levels of, GAL A enzyme results in the “classic” sub-type of Fabry disease. Classic Fabry disease typically has an early onset, which can occur in childhood or adolescence.
Commonly, the earliest signs and symptoms of classic Fabry disease can include:
Classic Fabry Disease
Late Onset Fabry Disease
Affected individuals whose GAL A enzyme is present at greater than 1% of normal levels have the more-or-less attenuated, later-onset sub-type of Fabry disease. They usually do not experience the classic sub-type early symptoms listed above. Rather, symptoms of kidney, heart or cerebrovascular involvement usually occur between the ages of 30 to 45. It is the first appearance of such kidney, heart or cerebrovascular symptoms that often leads to the initial diagnosis of late-onset Fabry disease. Males and affected females with late-onset Fabry disease may experience any of the following symptoms or complications.
NOTE: Individuals with the classic sub-type of Fabry disease may also add any of the following symptoms or complications to their early symptoms noted above as they age.
Source; Indications, Newsletter of the Lysosomal Disease Network, February 2014.
Read this article that discusses how a mutation is classified as Classic or Late-Onset. It also talks about prevalence of both subtypes.