A NULL MUTATION ALLELE IN THE CNTF GENE AND SCHIZOPHRENIC PSYCHOSES

THE maldevelopmental theory postulates disturbances in neural developm ent as crucial factors in the aetiopathogenesis of schizophrenia. Neur otrophic factors, including ciliary neurotrophic factor (CNTF), play a central role in the regulation of such development. A mutation has be en described for the CNTF gene, whereby subjects homozygous for the mu tation lack CNTF. The polymerase chain reaction was used to amplify th e CNTF gene region containing this mutation in whole blood genomic DNA . The mutation was detected by analysis of restriction fragment length polymorphisms. Patients suffering from schizophrenic psychosis (ICD-1 0 criteria) (51 from Wurzburg, 83 from Barcelona), and healthy control s (62 from Wurzburg, 50 from Barcelona) were investigated. In the Wurz burg group, the frequency of subjects homozygous or heterozygous for t he mutation was significantly higher among schizophrenic patients than in controls. However, no difference could be detected in the Spanish sample; the possible reasons for the different allele distribution in the two patient groups is discussed. It is concluded that the CNTF nul l mutation may be relevant to the aetiopathogenesis of schizophrenia i n some patients, but further work is required to identify specifically the patient group for which it is important.