SNP Shot: Genomic Insights

Spastic paraplegia type 31 belongs to a category of inherited conditions called hereditary spastic paraplegias. These conditions are defined by increasing muscle stiffness (spasticity) and eventual lower limb paralysis (paraplegia). This is due to the breakdown of motor neurons, the nerve cells that control muscle movement. Hereditary spastic paraplegias are classified as either pure or complicated. Pure forms primarily affect the legs, whereas complicated forms affect both legs and arms, and may involve the brain and other body parts. Spastic paraplegia type 31 is generally considered a pure form of hereditary spastic paraplegia, although some complicated presentations have been observed.

The onset of spastic paraplegia type 31 typically occurs before age 20 or after age 30. Initial symptoms often include walking difficulties resulting from spasticity and weakness, generally affecting both legs similarly. Individuals with this condition may also experience gradual muscle loss (amyotrophy) in the legs, heightened reflexes (hyperreflexia), reduced vibration sensitivity, bladder control issues, and high arches in their feet (pes cavus). As the condition advances, some individuals may require assistance with walking.

Inheritance:

Spastic paraplegia type 31 follows an autosomal dominant inheritance pattern. This means that only one copy of the mutated gene in each cell is necessary for the condition to develop.