By Joey Kim.
L1 Syndome is an inherited, X-linked disorder that is caused by mutations in the L1CAM gene and targets the nervous system. Although this disorder occurs exclusively in males at an incidence rate of 1 in 30,000, it has been reported that 5% of females who are carriers of the L1CAM gene mutation present with mild symptoms.
The disease is characterized by hydrocephalus (increased fluid in the center of the brain), spasticity of the lower limbs (muscle stiffness), adducted thumbs (clasped towards the palm), difficulty speaking, seizures, and an underdeveloped or absent corpus callosum. Individuals with this syndrome present with mild to moderate intellectual disabilities.
This syndrome is diagnosed by recognizing characteristic clinical and neuropathological symptoms. It is also established by looking at the individual’s family history for the X-linked inheritance. A molecular genetic test for the L1CAM gene can also be performed on a case by case basis.
Although there is no cure for L1, there are many options for disease management involving multidisciplinary teams that includes experts in pediatrics, child neurology, neurosurgery, rehabilitation, and medical genetics. For inviduals with hydrocephalus, cerebrospinal fluid (CSF) shunts help reduce intracranial pressure. Early intervention is important for children with L1 so it is advisable that services such as special education, social support, physical therapy, and other medical services are available.
Check out these links to learn more about L1 Syndrome
Joey Kim’s L1 Syndrome update on NORD:
Full L1 Syndrome report by GeneReviews: