Living with L1 syndrome
A group of nervous system conditions in males, ranging from fluid buildup in the brain to leg stiffness, caused by changes in an X-linked gene.
Understanding L1 syndrome
From most to least severe, the conditions are X-linked hydrocephalus (HSAS), MASA syndrome, spastic paraplegia type 1, and X-linked complicated corpus callosum agenesis. Features include fluid buildup in the brain (hydrocephalus), muscle stiffness, thumbs bent toward the palms, and intellectual disability that ranges from mild to severe. Some have seizures. It can be noticed during pregnancy, at birth, or in infancy.
Signs & symptoms
Symptoms vary from person to person. GARD lists these among the most common:
- Fluid buildup in the brain (hydrocephalus)
- Muscle stiffness (spasticity)
- Thumbs bent toward the palm
- Intellectual disability
- Developmental delay
- Language impairment
Not everyone has every symptom. GARD's list comes from the Human Phenotype Ontology.
Diagnosis
- 1Talk with your doctor
Share the symptoms you've noticed, when they started and your family health history. Notes and photos can help.
- 2See a specialist
Specialists who may be involved include brain and nervous system specialists and genetic specialists.
- 3Ask which tests can help
Your care team will decide which exams and tests can confirm the diagnosis.
Care & treatment
- Care team
- Brain and nervous system specialists (neurologists); Genetic specialists (geneticists)
- Expert care
- Ask about multidisciplinary care centers for rare conditions
- Treatment
- GARD doesn't list specific treatments for this condition. Your care team will tailor care to your symptoms.
- Research
- Clinical trials and observational studies may be options. See the research section below.
General information, not medical advice. Your care team makes the decisions.
Everyday life
Living with a rare condition is easier with support.
- Connect with rare disease patient organizations for support
- Keep notes on symptoms, changes and questions for appointments
- Ask about patient registries that help research
- Look into financial aid and travel resources for care visits
Quick facts
GARD says changes in genes (also called variants) cause this condition. It is X-linked, meaning the gene is on the X chromosome.
Also known as: corpus callosum hypoplasia-retardation-adducted thumbs-spasticity-hydrocephalus syndrome; crash syndrome; hypoplasia of corpus callosum and mental retardation with adducted thumbs and spasticity and hydrocephalus syndrome; hypoplasia of corpus callosum, intellectual disability, adducted thumbs, spasticity, hydrocephalus syndrome; l1cam syndrome
Patient organizations
Rare-disease groups that can help
- Global GenesRare Diseases · United States
- National Organization for Rare DisordersRare Diseases · United States
- Genetic AllianceRare Diseases · United States
- RARE FoundationRare Diseases · United States
You are more than your diagnosis
Perspectives from people navigating life with L1 syndrome.
Explore research for L1 syndrome
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- Recruiting studies from ClinicalTrials.gov
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- Eligibility is confirmed by the study team
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Powered by HealthSpark, our AI chat helper · Study information from ClinicalTrials.gov · Eligibility is confirmed by the study team.
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