OBJECTIVE: The few studies of bipolar I disorder in twins have consistently emphasized the genetic contribution to disease liability. The authors report what appears to be the first twin study of bipolar I disorder involving a population-based twin sample, in which the diagnoses were made by using structured, personal interviews. METHOD: All Finnish same-sex twins (N=19,124) born from 1940 to 1957 were screened for a diagnosis of bipolar I disorder as recorded in the National Hospital Discharge Register between 1969 and 1991 or self-reported in surveys of the Finnish Twin Cohort in 1975, 1981, and 1990. Thirty-eight pairs were thereby identified and invited to participate in the study; the participation rate was 68%. Lifetime diagnoses were made by using the Structured Clinical Interview for DSM-IV. The authors calculated probandwise and pairwise concordances and correlations in liability and applied biometrical model fitting. RESULTS: The probandwise concordance rates were 0.43 (95% CI=0.10 to 0.82) for monozygotic twins and 0.06 (95% CI=0.00 to 0.27) for dizygotic twins. The correlations in liability were 0.85 and 0.41, respectively. The model with no familial transmission was rejected. The best-fitting model was the one in which genetic and specific environmental factors explained the variance in liability, with a heritability estimate of 0.93 (95% CI=0.69 to 1.00). CONCLUSIONS: The high heritability of bipolar disorder was demonstrated in a nationwide population-based twin sample assessed with structured personal interviews.
OBJECTIVE: The few studies of bipolar I disorder in twins have consistently emphasized the genetic contribution to disease liability. The authors report what appears to be the first twin study of bipolar I disorder involving a population-based twin sample, in which the diagnoses were made by using structured, personal interviews. METHOD: All Finnish same-sex twins (N=19,124) born from 1940 to 1957 were screened for a diagnosis of bipolar I disorder as recorded in the National Hospital Discharge Register between 1969 and 1991 or self-reported in surveys of the Finnish Twin Cohort in 1975, 1981, and 1990. Thirty-eight pairs were thereby identified and invited to participate in the study; the participation rate was 68%. Lifetime diagnoses were made by using the Structured Clinical Interview for DSM-IV. The authors calculated probandwise and pairwise concordances and correlations in liability and applied biometrical model fitting. RESULTS: The probandwise concordance rates were 0.43 (95% CI=0.10 to 0.82) for monozygotic twins and 0.06 (95% CI=0.00 to 0.27) for dizygotic twins. The correlations in liability were 0.85 and 0.41, respectively. The model with no familial transmission was rejected. The best-fitting model was the one in which genetic and specific environmental factors explained the variance in liability, with a heritability estimate of 0.93 (95% CI=0.69 to 1.00). CONCLUSIONS: The high heritability of bipolar disorder was demonstrated in a nationwide population-based twin sample assessed with structured personal interviews.
Authors: Amit Anand; Daniel L Koller; William B Lawson; Elliot S Gershon; John I Nurnberger Journal: J Affect Disord Date: 2015-03-10 Impact factor: 4.839
Authors: Stephanie Nissen; Sherri Liang; Tatyana Shehktman; John R Kelsoe; Tiffany A Greenwood; Caroline M Nievergelt; Rebecca McKinney; Paul D Shilling; Erin N Smith; Nicholas J Schork; Cinnamon S Bloss; John I Nurnberger; Howard J Edenberg; Tatiana Foroud; Daniel L Koller; Elliot S Gershon; Chunyu Liu; Judith A Badner; William A Scheftner; William B Lawson; Evaristus A Nwulia; Maria Hipolito; William Coryell; John Rice; William Byerley; Francis J McMahon; Wade H Berrettini; James B Potash; Peter P Zandi; Pamela B Mahon; Melvin G McInnis; Sebastian Zöllner; Peng Zhang; David W Craig; Szabolics Szelinger; Thomas B Barrett; Thomas G Schulze Journal: Am J Med Genet B Neuropsychiatr Genet Date: 2012-10-04 Impact factor: 3.568
Authors: Yuval Neria; Mark Olfson; Marc J Gameroff; Priya Wickramaratne; Daniel Pilowsky; Helen Verdeli; Raz Gross; Julián Manetti-Cusa; Randall D Marshall; Rafael Lantigua; Steven Shea; Myrna M Weissman Journal: Bipolar Disord Date: 2008-06 Impact factor: 6.744