Question: What are the genetic changes related to progressive supranuclear palsy ?
Answer: In most cases, the genetic cause of progressive supranuclear palsy is unknown. Rarely, the disease results from mutations in the MAPT gene. Certain normal variations (polymorphisms) in the MAPT gene have also been associated with an increased risk of developing progressive supranuclear palsy. The MAPT gene provides instructions for making a protein called tau. This protein is found throughout the nervous system, including in nerve cells (neurons) in the brain. It is involved in assembling and stabilizing microtubules, which are rigid, hollow fibers that make up the cell's structural framework (the cytoskeleton). Microtubules help cells maintain their shape, assist in the process of cell division, and are essential for the transport of materials within cells. The signs and symptoms of progressive supranuclear palsy appear to be related to abnormalities in the tau protein. In people with MAPT gene mutations, genetic changes disrupt the protein's normal structure and function. However, abnormal tau is also found in affected individuals without MAPT gene mutations. The defective tau protein assembles into abnormal clumps within neurons and other brain cells, although it is unclear what effect these clumps have on cell function and survival. Progressive supranuclear palsy is characterized by the gradual death of brain cells, particularly in structures deep within the brain that are essential for coordinating movement. This loss of brain cells underlies the movement abnormalities and other features of progressive supranuclear palsy. This condition is one of several related diseases known as tauopathies, which are characterized by an abnormal buildup of tau in the brain. Researchers suspect that other genetic and environmental factors also contribute to progressive supranuclear palsy. For example, the disease has been linked to genetic changes on chromosome 1 and chromosome 11. However, the specific genes involved have not been identified.
Source: GHR