Deficiency of α-Galactosidase is the cause of Fabry’s disease. Fabry’s disease is an inherited condition that affects only a few thousand people worldwide. Fabry’s disease causes a wide range of signs and symptoms that can range from mild to severe and life-threatening.
Anderson-Fabry disease is an X-linked recessive inborn error of glycosphingolipid metabolism caused by deficiency of alpha-galactosidase A. The enzyme deficiency leads to defective storage of sphingolipid and progressive endothelial accumulation causing abnormalities in the skin, eye, kidney, heart, brain and peripheral nervous system.
The gene responsible for alpha-galactosidase is located on the long arm of the X chromosome. There have been almost 200 mutations identified. It is estimated to occur in 1 in 55,000 males in the classical form but the atypical variant may be more common. As an X-linked recessively inherited condition female carriers exist and can exhibit mild-to-moderate symptoms. Depending on the type presentation can occur up to adulthood. Common signs and symptoms consist of:- slight builds with characteristic coarse facial features and delayed puberty, paraesthesia in the extremities, general fatigue and weakness, usually present with cardiac involvement including cardiomegaly, mitral insufficiency, and cardiomyopathy, proteinuria. Some success in treating the disease has been achieved with enzyme replacement therapy.
White Cell:10 – 50 µmol/g/hour
Plasma: 3 – 20 umol/L/hour
Blood spot: 6.3 – 47 pmol/punch/hour
White Cell & Plasma: Whole Blood – EDTA
Blood Spot: collected on Whatman 903 specimen collection paper (Genzyme) – available from Special Biochemistry Office.
Note that blood can be spotted at source or from EDTA tube in lab – ensure that enough blood spotted to be visible on both sides of card.