Tay-Sachs Disease 2011
Contents
Summary
The Tay-Sachs disease (TSD) is a rare autosomal, recessive genetic disorder which is caused by accumulation of lipids in the brain. This leads to the cell death of those neurons. There exist three different variations of the TSD. The most common one is the Infantile Tay-Sachs disease which affects death of the children under the age of 5. The two other variants are the Juvenile and Adult/Late Onset TSD, which are less aggressive. The disease causes a deterioration of mental and physical abilities. Sadly, there currently exists no treatment.
Phenotype
Infantile Tay-Sachs disease:
The most common and aggressive form of TSD is the infantile TSD, which has a lot of different symptoms and leads to the early death of the affected children. The most common symptoms are:
- normal development in the first six month after birth
- "cherry-red" macula
- paralysis
- dementia
- blindness
- deafness
- muscle atrophy
- startle response to sound stimuli
- inability to coordinate muscle movement (child can't roll over and sit)
- death in the second or third year
Juvenile and Adult TSD:
This forms of the Tay-Sachs disease occur later in lifetime. These two forms were not always recogniced as variants of the TSD. The symptomes of these forms are less aggressive. Often the patients become wheelchair users and have some psychiatric and physical limitation, which could be handled with drugs.
Cross-references
See also description of this disease in
Biochemical disease mechanism
The example protein is involved in the hydrolysis of terminal N--hexosamines. It is a heterodimer consisting one alpha subunit (encoded by HEXA) and one beta subunit (encoded by HEXB). The enzyme is responsible for the degradation of GM2 gangliosides (which are fatty acid derivatives) and other molecules in the brain and the tissue. More precisely the enzyme breaks down the phospholipids. If the enzyme is defect it leads to an accumulation of GM2 gangliosides in the neurons, which affect the death of those cells.
Cross-references
Mutations
Current knowledge about mutations associated with the disease. - Separate into disease causing and neutral mutations.
Reference sequence
Which sequence does not cause the disease and is most often found in the population.
- Create a page for the reference sequence. -- These sequence pages will be the starting point for collecting prediction results and result discussions.
