spastic paraplegia, autosomal recessive, type 7

spastic paraplegia, autosomal recessive, type 7

A complex, usually autosomal dominant, but also recessive and X-linked, form (OMIM:607259) of spastic paraplegia, a neurodegenerative spinal cord disease characterised by a slow, gradual, progressive weakness and spasticity of the lower limbs; initial symptoms include difficulty with balance, weakness and stiffness in legs, muscle spasms, and dragging of toes when walking. Some forms are characterised by urinary incontinence or weakness and stiffness in other parts of the body; type 7 is characterised by onset between age 25–40, variably accompanied by cerebellar syndrome, supranuclear palsy and cognitive impairment, with disturbance of attention and executive functions.
 
Molecular pathology
Caused by defects of SPG7, which encodes a mitochondrial metalloprotease thought to have roles in membrane trafficking, intracellular motility, organelle biogenesis, protein folding and proteolysis.