PCR identified Cpn outer membrane protein gene in the CSF of 97% of MS patients and 18% of controls, and ELISA showed that 86% of MS patients had Cpn antibodies in their CSF.[46] The results were called into question after other centers failed to identify Cpn by PCR or culture in CSF and autopsy specimens of MS patients,[54, 55] but this could be attributed to technical variations.[56] Since then, several centers have continued to report the association of Cpn with MS while others have not found one. The gene discussed is CPN1; the disease is myeloid sarcoma.