Encyclopedia
Fucosidosis is a neurodegenerative disorder which progresses inexorably. Clinical features include coarse facial features, growth retardation, recurrent upper respiratory infections, dysostosis multiplex, and angiokeratoma corporis diffusum.
- Fucosidosis
- neurodegenerative disorder
- FUCA1 gene
1. Introduction
Fucosidosis is caused by mutations in the FUCA1 gene resulting in α-L-fucosidase deficiency. Only 36 pathogenic variants in the FUCA1 gene are related to fucosidosis. Most of them are missense/nonsense substitutions; six missense and 11 nonsense mutations. Among deletions there were eight small and five gross changes. So far, only three splice site variants have been described—one small deletion, one complete deletion and one stop-loss mutation. The disease has a significant clinical variability, the cause of which is not well understood. The genotype–phenotype correlation has not been well defined.
2. Frequency
Fucosidosis is a rare condition; approximately 100 cases have been reported worldwide. This condition appears to be most prevalent in Italy, Cuba, and the southwestern United States.
3. Causes
Mutations in the FUCA1 gene cause fucosidosis. The FUCA1 gene provides instructions for making an enzyme called alpha-L-fucosidase. This enzyme plays a role in the breakdown of complexes of sugar molecules (oligosaccharides) attached to certain proteins (glycoproteins) and fats (glycolipids). Alpha-L-fucosidase is responsible for cutting (cleaving) off a sugar molecule called fucose toward the end of the breakdown process.
FUCA1 gene mutations severely reduce or eliminate the activity of the alpha-L-fucosidase enzyme. A lack of enzyme activity results in an incomplete breakdown of glycolipids and glycoproteins. These partially broken down compounds gradually accumulate within various cells and tissues throughout the body and cause cells to malfunction. Brain cells are particularly sensitive to the buildup of glycolipids and glycoproteins, which can result in cell death. Loss of brain cells is thought to cause the neurological symptoms of fucosidosis. Accumulation of glycolipids and glycoproteins also occurs in other organs such as the liver, spleen, skin, heart, pancreas, and kidneys, contributing to the additional symptoms of fucosidosis.
4. Inheritance
This condition is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations. The parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but they typically do not show signs and symptoms of the condition.
5. Other Names for This Condition
- Alpha-fucosidase deficiency
- Fucosidase deficiency
- Fucosidase Deficiency Disease
This entry is adapted from the peer-reviewed paper https://medlineplus.gov/genetics/condition/fucosidosis
References
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- Bharati A, Higgins C, Ellis I, Wraith J. Fucosidosis: a therapeutic challenge.Pediatr Dermatol. 2007 Jul-Aug;24(4):442-3.
- Cragg H, Williamson M, Young E, O'Brien J, Alhadeff J, Fang-Kircher S, PaschkeE, Winchester B. Fucosidosis: genetic and biochemical analysis of eight cases. J Med Genet. 1997 Feb;34(2):105-10.
- Galluzzi P, Rufa A, Balestri P, Cerase A, Federico A. MR brain imaging offucosidosis type I. AJNR Am J Neuroradiol. 2001 Apr;22(4):777-80.
- Kanitakis J, Allombert C, Doebelin B, Deroo-Berger MC, Grande S, Blanc S,Claudy A. Fucosidosis with angiokeratoma. Immunohistochemical &electronmicroscopic study of a new case and literature review. J Cutan Pathol.2005 Aug;32(7):506-11.
- Willems PJ, Gatti R, Darby JK, Romeo G, Durand P, Dumon JE, O'Brien JS.Fucosidosis revisited: a review of 77 patients. Am J Med Genet. 1991Jan;38(1):111-31. Review.
