Paraplegia familial spastic type 4 (Spastic paraplegia type 4 -SPG4-) - Gen SPAST.  

Paraplegia (or paraparesis) familial spastic type 4 (SPG4) is one of spastic paraplegia known as heritable genetic damage. These changes are characterized by spasticity and development of paraplegia. Hereditary spastic paraplegia the are divided into two types: pure and complex. Pure types involving the lower extremities. Complex types involving the lower extremities and may affect the upper extremities to a lesser degree. Spastic paraplegia complex the also affect the structure or function of the brain and peripheral nervous system.

The spastic paraplegia type 4 is a hereditary spastic paraplegia pure. This disease involves spasticity of leg muscles and muscle weakness. People with this disorder may also have hyperreflexia, spasms ankles, lifting arch and decreased bladder control. Spastic paraplegia type 4 usually affects nerve and muscle in the lower half of the body function.

This process is due to mutations in the gene SPAST, located on the short arm of chromosome 2 (2p24-p21)., Encoding spastin protein. This protein is found throughout the body, particularly in certain neurons, where it plays a role in the function of microtubules that form the cell cytoskeleton. Microtubules are also involved in the transport of components of cells and facilitate cell division. Protein is likely to help restrict the length of microtubules and disassembling the microtubule structures when they are no longer needed.

They have identified more than 240 mutations in the gene causing the SPAST spastic paraplegia type 4 gene mutations SPAST are responsible for about 40% of spastic paraplegia the autosomal dominant inheritance. Most of these mutations alter the structure or disrupt the production of spastin, altering its ability to regulate microtubule. It is believed that the inability of microtubules to transport cell components, especially in nerve cells contributes to the main signs and symptoms of the disease.

This disease is inherited as an autosomal dominant, which means that a copy of the altered gene in each cell is sufficient to cause the alteration. In most cases, an affected person inherits the mutation from an affected parent. The remaining cases can be due to new mutations in the gene. These cases occur in people with no history of disease in your family.  

Tests in IVAMI: in IVAMI perform detection of mutations associated with spastic paraplegia type 4 by the complete PCR amplification of exons SPAST gene, and subsequent sequencing.

Samples recommended: EDTA blood collected for separation of blood leukocytes, or impregnated sample card with dried blood (IVAMI may mail the card to deposit the blood sample).