The Wolfram syndrome (WS) is an autosomal recessive disorder beginning in childhood that consists of four clinical features: diabetes insipidus, diabetes mellitus, optic atrophy and deafness. Its pathogenesis remains unknown, although the tendency to develop this syndrome has been related to some class II antigens of the HLA system. We report six new cases in four families. A review of published data from the genetic features of this syndrome is performed, establishing the high frequency of the HLA-DR2 antigen in the WS (44.4%) compared with a control group (21.9%; relative risk, 2.8) and to patients with Type 1 insulin-dependent diabetes mellitus (Type 1 diabetes) (6.77%; relative risk, 9.7). We also comment the high frequency of the HLA-DQw1 antigen (85.5%) in this syndrome, without statistical significance. A familial segregation study of the HLA haplotypes has been carried out without finding correlation between the autosomal recessive pattern attributed to the WS, and the major histocompatibility complex. In conclusion, whereas HLA may increase susceptibility to the WS, as shown by the existence of an HLA-DR2 association, the major genetic influence on the inheritance of the WS must be at another locus.