spastic paraplegia 18—autosomal recessive
A severe form (OMIM:611225) of spastic paraplegia* with onset in early childhood, typically with severe psychomotor retardation, variably accompanied by significant joint contractures.
*A neurodegenerative disorder with a highly variable rate of progression and severity of symptoms, which is characterised by a slow, gradual, progressive weakness and spasticity of the lower limbs. Initial symptoms may include difficulty with balance, weakness and stiffness in the legs, muscle spasms, and toe dragging when walking. In some forms of spastic paraplegia, bladder symptoms, including incontinence may appear, or the weakness and stiffness may spread to other parts of the body.
Molecular pathology Defects of ERLIN2, which encodes a lipid raft-associated protein that plays a critical role in inositol 1,4,5-trisphosphate–IP3 signaling, cause spastic paraplegia 18—autosomal recessive.
Synonym Intellectual disability—motor dysfunction—and joint contractures