The brain changes in Progressive Supranuclear Palsy and Corticobasal Degeneration are similar but not the same.
Genetics
Tau protein is found naturally in the nervous system of the body and in the neurons of the brain. Tau plays an important role in the structure and function of the cells. Research has shown that the signs and symptoms experienced in PSP and CBD are due to abnormalities in tau protein.
The MAPT gene is responsible for making tau. If the MAPT gene mutates changes can occur that result in abnormal clumping within the neurons and brain cells. This results in the gradual death of brain cells. It is this loss of brain cells that is responsible for changes in coordinating movement, personality and cognition in PSP and CBD.
Gene changes on Chromosome 1, 11 and 17 have also been implicated but the specific genes have not yet been identified. Other genetic and environmental factors appear to be necessary but as yet no definitive answer has been found. In most cases of PSP the cause is unknown.
Inheritance
PSP and CBD occur by chance and usually there is no history of the disorder. It is uncommon to have more than one family member with PSP but where it does occur in families, research has shown that at least three genes could be responsible for the disease to develop. There is no evidence to date that CBD is inherited.
Research
Some research aims at developing drugs to prevent tau aggregation or alter tau function. A major research project by geneticists at the University of Pennsylvania are trying to decipher exomes from a large sample of material from patients with PSP . Exome analysis is very useful to identify disease related changes in DNA. The results should bring us closer to finding a cause and developing better drugs to target the disease.
Dublin Brain Bank
Progressive Supranuclear Palsy is difficult to diagnose and conclusive identification is often only available after post-mortem. Brain donation is vital to help understand the disease and find a cure. It is a difficult decision to make and needs to be discussed with the family. However many people choose to donate. People who live with this disease often want to find a cure so no one else has to go down the same road. In Ireland we are lucky to have the Dublin Brain Bank at the Beaumont Hospital. www.brainbank.ie
PSPA Ireland 