title: Evidence of genetic susceptibility to infectious mononucleosis: a twin study.
abstract: Infectious mononucleosis is a clinical manifestation of primary Epstein-Barr virus infection. It is unknown whether genetic factors contribute to risk. To assess heritability, we compared disease concordance in monozygotic to dizygotic twin pairs from the population-based California Twin Program and assessed the risk to initially unaffected co-twins. One member of 611 and both members of 58 twin pairs reported a history of infectious mononucleosis. Pairwise concordance in monozygotic and dizygotic pairs was respectively 12·1% [standard error (s.e.)=1·9%] and 6·1% (s.e.=1·2%). The relative risk (hazard ratio) of monozygotic compared to dizygotic unaffected co-twins of cases was 1·9 [95% confidence interval (CI) 1·1-3·4, P=0·03], over the follow-up period. When the analysis was restricted to same-sex twin pairs, that estimate was 2·5 (95% CI 1·2-5·3, P=0·02). The results are compatible with a heritable contribution to the risk of infectious mononucleosis.
authors.affiliation: Department of Preventive Medicine and Norris Comprehensive Cancer Centre, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA.
authors.forename: A E
authors.initials: AE
authors.lastname: Hwang
authors.forename: A S
authors.initials: AS
authors.lastname: Hamilton
authors.forename: M G
authors.initials: MG
authors.lastname: Cockburn
authors.forename: R
authors.initials: R
authors.lastname: Ambinder
authors.forename: J
authors.initials: J
authors.lastname: Zadnick
authors.forename: E E
authors.initials: EE
authors.lastname: Brown
authors.forename: T M
authors.initials: TM
authors.lastname: Mack
authors.forename: W
authors.initials: W
authors.lastname: Cozen
mesh_terms: D000293:Adolescent; D000328:Adult; D002140:California; D005260:Female; D005500:Follow-Up Studies; D020022:Genetic Predisposition to Disease; D006801:Humans; D007244:Infectious Mononucleosis / Q000235:genetics*; D008297:Male; D016016:Proportional Hazards Models; D012042:Registries; D012306:Risk; D057566:Self Report; D014429:Twins, Dizygotic; D014430:Twins, Monozygotic; D055815:Young Adult