This website provides information on patients with mutations in the NFASC gene, including clinical data, molecular data, management and research options.

The syndrome caused by mutations in the NFASC gene is a multisystem neurodevelopmental disorder characterized by a spectrum of central (intellectual disability, developmental delay, motor impairment, speech difficulties) and peripheral (early onset demyelinating neuropathy) neurological involvement.

In all patients identified so far in our genetic studies, psychomotor development was severely delayed in all domains. Affected individuals did not communicate, and none achieved purposeful hand movements or independent ambulation. Hypotonia was present from neonatal age in all cases. Impaired social interaction and only brief and occasional visual contact were noticed in all affected individuals by the first year of age. Several patients developed restricted patterns of interests and repetitive behaviours and frequently exhibited hand or head stereotypies. Moderate to severe intellectual disability was documented in all cases. None of the affected individuals attained intelligible speech. Because of muscle weakness and absent reflexes, individuals from 4 unrelated families underwent detailed neurophysiological investigations as part of their diagnostic work-up and these showed a severe reduction in peripheral nerve conduction velocities in all cases. Patients from 2 families so far exhibited the most profound phenotype with severe demyelinating and axonal neuropathy at neurophysiological investigations. Non-specific EEG abnormalities including slow background activities were observed in several families although affected individuals had no history of seizures.

Not all individuals with a mutation in the NFASC gene have these features.

This website was created to share and collect information about clinic, management and research projects to gather more knowledge and provide better treatment of patients with mutations in the NFASC gene.

Stephanie Efthymiou, PhD, Department of Neuromuscular Disorders, UCL Queen Square Institute of Neurology, London, UK, s.efthymiou@ucl.ac.uk

Henry Houlden, MD, PhD, Department of Neuromuscular Disorders, UCL Queen Square Institute of Neurology, London, UK, h.houlden@ucl.ac.uk