Intrathecal passive transfer of monoclonal GAD-Ab representing an epitope specificity characteristic for SPS or purified immunoglobulin from sera from GAD-Ab-positive SPS patients impair spinal cord activity, induce a SPS-like syndrome with motor hyperexcitability, change behavior, and cognitive operations [34, 35, 37, 59, 60]. The gene discussed is GAD1; the disease is stiff-person syndrome.