HL‐A Antigens in Retinoblastoma

Twenty-one HL–A antigens of the first and the second HL–A series have been studied in a total of 122 German children with retinoblastoma and in 64 families. The frequency of antigen W5 was significantly increased (P < 0.001) and that of HL–A12 was significantly decreased (P < 0.001) in the patients than in healthy controls. The presence of W5 and the absence of HL–A12 may be among the factors influencing the penetrance of the retinoblastoma allele (hereditary form) or could in some way produce, together with several other unknown factors, an increased susceptibility to the disease, possibly through a defect in the immune response towards the tumor. Such correlations, however, must be very complex, since segregation analysis and family studies of patients with the hereditary and the nonhereditary form of the tumor failed to demonstrate clear-cut correlations between HL–A antigens and the incidence of the tumor.