Human cytomegalovirus DNA in the temporal cortex of a schizophrenic patient.

Using highly sensitive nucleic acids hybridization techniques, which allow the detection of 0.1-0.5 single copy gene equivalents per cell, DNA from the temporal cortex of seven definite schizophrenics, five persons with schizophrenia-like psychoses, three patients with Huntington's chorea and nine mentally normal individuals were probed with human cytomegalovirus (HCMV) DNA. A clear hybridization signal was obtained with DNA from the temporal lobe of a young schizophrenic patient, whereas DNA from the temporal cortex of controls did not hybridize to the HCMV probe. This finding is in agreement with the cytomegalovirus hypothesis of schizophrenia and hints at the possibility that viral infection of the temporal cortex may in some sporadic cases be a contributing factor to the development of schizophrenic psychoses. There is no indication, however, that infection of the central nervous system with HCMV is an aetiological factor in the great majority of schizophrenic disorders. Clearly further studies, preferably in situ hybridizations of whole brains, are needed to prove or disprove the cytomegalovirus hypothesis of schizophrenia.