HLA antigens as possible markers of heterogeneity in schizophrenia.

The distribution of HLA-A-, B- -and -C-locus antigens was tested in 200 male patients with final diagnosis of schizophrenia. A significant increase of HLA-A28 and HLA-Cw4 antigens and haplotype A10--B18 was found. Indications were obtained for the increase of HLA-A1 in hebephrenic patients. It was presumed that the increase of CW4 represents the common denominator of the diverse findings on paranoid schizophrenia. The increase of CW4 indicates that the paranoid schizophrenia disease susceptibility locus is either the C locus itself or another closely linked locus (or loci). This would stress the importance of the HLA 'central' regions for HLA and disease associations. A hypothesis is presented which points to the possibility that HLA antigens could be genetic markers of three ethiopathogenetic subgroups of schizophrenia. The possible tests of this hypothesis are also suggested.