Inclusion Criteria:
* Clinical diagnosis of Snijders Blok-Campeau syndrome
* Heterozygous mutation of c.3073C\>T, p.(Arg1025Trp) in the CHD3 gene
* Normal liver, heart and immune function
* Normal coagulation and platelet counts
Exclusion Criteria:
* Brain tumor or intracranial space-occupying lesion
* Contraindications to administration of lumbar puncture or sheath injection administration
* Persistent status epilepticus or recurrent epileptic control instability
* Presence of unstable systemic disease including active bacterial, fungal or HIV, hepatitis A, hepatitis B infection
* Serum anti-AAV neutralizing antibody titer \>1:50 (ELISA immunoassay)
* Treatment with immunological agents other than protocol-specified prophylaxis within 3 months
* Prior gene therapy
* Participation in another clinical trial, or treatment with another investigational product within 30 days or 5 half-lives
* Known allergy to any investigational product
View Inclusion and Exclusion Criteria at ClinicalTrials.gov