Sandhoff Disease
Sandhoff Disease Causes
Sandhoff disease is caused by mutations in the HEXB gene. This gene is primarily responsible for controlling the production of beta-hexosaminidase A and beta-hexosaminidase B, two enzymes that break down fatty substances, complex sugars, and other molecules that are linked to sugars. HEXB gene mutations disturb the normal functioning of these enzymes, leading to a toxic level buildup of GM2 ganglioside (fatty compound broken down by beta-hexosaminidase A) and other compounds inside cells.
Sandhoff Disease Definition
Sandhoff disease is a genetic autosomal recessive disorder affecting lipid storage, leading to progressive damage in the nerve cells of the brain and spinal cord.
Sandhoff Disease Diagnosis
Sandhoff disease can be diagnosed through a biopsy of sample tissues from the liver. Cells and tissues can be molecularly analyzed to screen for a genetic metabolic disorder. An enzyme assay, genetic testing, and occasionally a urinalysis are also common diagnostic steps.
Sandhoff Disease Symptoms and Signs
The most common and severe type of Sandhoff disease occurs during infancy, particularly at age 3-6 months old, at which time development slows and muscles weaken. As Sandhoff disease progresses, affected infants develop seizures, hearing loss, vision impairment, mental retardation, and paralysis. Cherry-red spot, a type of eye abnormality, is a characteristic sign of Sandhoff disease. In some cases, affected infants show bone abnormalities and/or enlarged organs. Other types of Sandhoff disease are relatively rare. Symptoms may appear in childhood, adolescence or adulthood, but are often milder than those in infantile Sandhoff disease. As in the infantile form, common symptoms include motor weakness, mental deterioration, speech problems, ataxia (loss of muscle coordination) and other related problems.
Sandhoff Disease Treatment
There is currently no specific treatment to cure Sandhoff disease. However, an affected patient needs to maintain proper nutrition, clear airways, and hydration. Anticonvulsants are sometimes advised to control seizures. Appropriate medication is also used to treat respiratory infections.