Cederroth CR, et al. - Researchers examined 11,060 adoptees, 19,015 adoptive parents, and 17,025 biological parents to assess the relationship of clinically significant tinnitus with genetic factors and to estimate the genetic risk in the transmission of tinnitus. The prevalence of diagnosed tinnitus was 2.2% among 1,029 patients. They determined mean (SE) heritability of 31% (14%) by using tetrachoric correlations. They suggested an association of genetic factors with the familial clustering of clinically significant tinnitus with no shared-environment association. An association might be seen between the transition from negligible to severe tinnitus and genetic constituents.