The L1 syndrome may manifest itself as one of several phenotypes. One of these is X-Linked Complicated Hereditary Spastic Paraplegia Type 1.
Genetic defect: L1CAM (L1 cell adhesion molecule)
Location: Xq28
Inheritance: X-linked (affected males, carrier females)
Features of X-Linked Complicated Hereditary Spastic Paraplegia Type 1:
(1) mild to moderate intellectual impairment
(2) hypotonia progressing to spastic paraplegia (with shuffling gait)
An MRI of the brain is normal.
Differential diagnosis:
(1) spastic paraplegia 2 (SPG2)
