Concordance for hodgkin\u27s disease in identical twins suggesting genetic susceptibility to the young-adult form of the disease

Background: Relatives of young adults with Hodgkin\u27s disease are at increased risk of Hodgkin\u27s disease, and lines of evidence implicate both inheritance and environment. Methods: We have identified and followed 432 sets of twins affected by Hodgkin\u27s disease. The number of cases of Hodgkin\u27s disease observed before the age of 50 years in the healthy monozygotic and dizygotic twins of the patients with Hodgkin\u27s disease was compared with the number expected from national age-specific incidence rates. Results: None of the 187 pairs of dizygotic twins became concordant for Hodgkin\u27s disease, whereas 10 of the 179 pairs of monozygotic twins did; in 5 of these pairs, the second case appeared after the original ascertainment. During the observation period, 0.1 (monozygotic) and 0.1 (dizygotic) cases in the unaffected twins were expected. Monozygotic twins of patients with Hodgkin\u27s disease thus had a greatly increased risk (standardized incidence ratio, 99; 95 percent confidence interval, 48 to 182), whereas no increase in the risk for dizygotic twins of patients with Hodgkin\u27s disease was observed. Conclusions: Genetic susceptibility underlies Hodgkin\u27s disease in young adulthood., Hodgkin\u27s disease is likely to have different causes in young adulthood and old age.1 The characteristic clinical presentation and histopathological appearance suggest that in young adults the disease is initiated by an environmental exposure, possibly to an infectious agent. The age-specific incidence during young adulthood varies over time and according to place and social class, much like that of infections. Those affected have a small average number of siblings, may not have had the common childhood infections, and are likely to have a history of infectious mononucleosis.2 These findings have been interpreted to suggest that Hodgkin\u27s disease may occur as… © 1995, Massachusetts Medical Society. All rights reserved