Fabry disease is a genetic condition that causes progressive health issues. Fabry disease impacts the skin, nerves, kidneys, heart, and brain in both men and women. Fabry disease occurs when an individual has a disease-causing change (pathogenic variant/mutation) in the GLA gene resulting in the body making too little of a specific enzyme called alpha-galactosidase A or A-gal. If there is not enough of this enzyme, the body is unable to break down certain large molecules such as globotriaosylceramide (GL-3/Gb3) and so they build up in the cells that line blood vessels and other parts of the body. This build up narrows the blood vessels, interferes with cell function, and causes cells to send out distress signals to the immune system.

Fabry disease related health issues can start at any age. Based on the timing of when symptoms begin and the combination of the medical issues, Fabry disease is divided into 2 types: classic Fabry disease and non-classic, also called later-onset, Fabry disease. Classic Fabry disease symptoms typically begin in childhood and progress to end organ damage in early adulthood. Nonclassic Fabry disease symptoms usually begin after childhood and can be more variable.