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Wiener klinische Wochenschrift

, Volume 119, Issue 15–16, pp 463–475 | Cite as

Genetics of suicide: a systematic review of twin studies

  • Martin VoracekEmail author
  • Lisa Mariella Loibl
Original Article

Summary

OBJECTIVES: Convergent evidence from a multitude of research designs (adoption, family, genomescan, geographical, immigrant, molecular genetic, surname, and twin studies of suicide) suggests genetic contributions to suicide risk. The present account provides a comprehensive and up-to-date review of the twin studies on this topic. METHODS: A total of 32 studies (19 case reports, 5 twin register-based studies, 4 population-based epidemiological studies, 4 studies of surviving co-twins) located through extensive literature search strategies are summarized and discussed here. This literature corpus was published between 1812 and 2006 in six languages and reports data from 13 countries. RESULTS: A meta-analysis of all register-based studies and all case reports aggregated shows that concordance for completed suicide is significantly more frequent among monozygotic than dizygotic twin pairs. The results of co-twin studies rule out exclusively psychosocially based explanations of this pattern. Population-based epidemiological studies demonstrate a significant contribution of additive genetic factors (heritability estimates: 30–55%) to the broader phenotype of suicidal behavior (suicide thoughts, plans and attempts) that largely overlaps for different types of suicidal behavior and is largely independent of the inheritance of psychiatric disorders. Nonshared environmental effects (i.e. personal experiences) also contribute substantially to the risk of suicidal behavior, whereas effects of shared (family) environment do not. CONCLUSIONS: The totality of evidence from twin studies of suicide strongly suggests genetic contributions to liability for suicidal behavior. To further research progress in this area, an extensive discussion of design limitations, shortcomings of the literature and further points is provided, including sources of bias, gaps in the literature, errors in previous reviews, age and sex effects and twin-singleton differences in suicide risk, and notes from a history-of-science view.

Keywords

Genetics Heritability Meta-analysis Suicide Systematic review Twins 

Genetische Faktoren bei Suizid: ein systematischer Überblick der Zwillingsstudien

Zusammenfassung

HINTERGRUND: Übereinstimmende Befunde aus einer Vielzahl von Forschungsdesigns (Adoptions-, Familien-, Migranten- und Zwillingsstudien sowie Genom-Scans, familiennamenbasierte, geografische und molekulargenetische Studien) weisen auf eine Beteiligung genetischer Risikofaktoren für Suizid hin. Dieser Beitrag bietet einen ausführlichen und aktuellen Überblick über die zu diesem Thema vorhandenen Zwillingsstudien. METHODEN: Über extensive Literatursuche wurden insgesamt 32 Studien (19 Fallberichte, 5 zwillingsregisterbasierte Studien, 4 populationsbasierte epidemiologische Studien, 4 Studien überlebender Ko-Zwillinge) eruiert, die hier zusammengefasst und diskutiert werden. Dieses Literaturkorpus wurde zwischen 1812 und 2006 in 6 verschiedenen Sprachen publiziert und enthält Daten aus 13 Ländern. ERGEBNISSE: Eine Meta-Analyse aller zwillingsregisterbasierten Studien und aller Fallberichte aggregiert zeigt, dass eineiige Zwillinge signifikant häufiger für Suizid konkordant sind als zweieiige Zwillinge. Ausschließlich psychosoziale Erklärungen für diesen Befund werden durch die Ergebnisse von Ko-Zwillingsstudien ausgeschlossen. Populationsbasierte epidemiologische Studien zeigen einen signifikanten Beitrag genetischer Faktoren (geschätzte Heritabilität: 30–55%) für den weitergefassten Phänotyp suizidalen Verhaltens (Suizidgedanken, Suizidpläne, Suizidversuche), der für die verschiedenen Typen suizidalen Verhaltens weitgehend überlappt und von der Vererbung psychiatrischer Erkrankungen weitgehend unabhängig ist. Effekte nicht-geteilter Umwelt (persönliche Lebenserfahrungen) tragen ebenfalls substantiell zum Risiko für suizidales Verhalten bei, nicht jedoch Effekte geteilter Umwelt (Familie). SCHLUSSFOLGERUNG: Die Gesamtheit der Befunde aus Zwillingsstudien zu Suizid legt sehr deutlich eine Beteiligung genetischer Faktoren an der Anfälligkeit zu suizidalem Verhalten nahe. Beschränkungen der Zwillings-Methode, Mängel der Literatur und weitere Punkte werden zur Förderung des Forschungsfortschritts in diesem Bereich ausführlich diskutiert (u.a.: Bias-Quellen und Leerstellen in der Literatur, Fehler in früheren Überblicksarbeiten, Alters- und Geschlechtseffekte sowie Zwillingsbesonderheiten bezüglich Suizidrisiko, wissenschaftsgeschichtlicher Kommentar).

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References

  1. Voracek M, Sonneck G (2006) Medical and psychology students' disbelief in the inheritance of risk factors for suicide. Psychol Rep 99: 599–602PubMedCrossRefGoogle Scholar
  2. Kõlves K, Tran US, Voracek M (2007) Knowledge about suicide and local suicide prevalence: a comparison of Estonia and Austria. Percept Mot Skills 105: 3–7PubMedGoogle Scholar
  3. Turecki G (2001) Suicidal behavior: is there a genetic predisposition? Bipolar Disord 3: 335–349PubMedCrossRefGoogle Scholar
  4. Baldessarini RJ, Hennen J (2004) Genetics of suicide: an overview. Harv Rev Psychiatry 12: 1–13PubMedGoogle Scholar
  5. Brent DA, Mann JJ (2005) Family genetic studies, suicide, and suicidal behavior. Am J Med Genet C: Semin Med Genet 133C: 13–24CrossRefGoogle Scholar
  6. Joiner TE, Brown JS, Wingate LR (2005) The psychology and neurobiology of suicidal behavior. Annu Rev Psychol 56: 287–314PubMedCrossRefGoogle Scholar
  7. Bondy B, Buettner A, Zill P (2006) Genetics of suicide. Mol Psychiatry 11: 336–351PubMedCrossRefGoogle Scholar
  8. Li D, He L (2006) Further clarification of the contribution of the tryptophan hydroxylase (TPH) gene to suicidal behavior using systematic allelic and genotypic meta-analyses. Hum Genet 119: 233–240PubMedCrossRefGoogle Scholar
  9. Hesselbrock V, Dick D, Hesselbrock M, Foroud T, Schuckit M, Edenberg H, et al (2004) The search for genetic risk factors associated with suicidal behavior. Alcohol Clin Exp Res 28 [Suppl]: 70S–76SPubMedCrossRefGoogle Scholar
  10. Cheng R, Juo SH, Loth JE, Nee J, Iossifov I, Blumenthal R, et al (2006) Genome-wide linkage scan in a large bipolar disorder sample from the National Institute of Mental Health genetics initiative suggests putative loci for bipolar disorder, psychosis, suicide, and panic disorder. Mol Psychiatry 11: 252–260PubMedCrossRefGoogle Scholar
  11. Marušič A, Farmer A (2001) Genetic risk factors as possible causes of the variation in European suicide rates [editorial]. Br J Psychiatry 179: 194–196PubMedCrossRefGoogle Scholar
  12. Voracek M, Fisher ML, Marušič A (2003) The Finno-Ugrian suicide hypothesis: variation in European suicide rates by latitude and longitude. Percept Mot Skills 97: 401–406PubMedGoogle Scholar
  13. Voracek M, Formann AK (2004) Variation in European suicide rates is better accounted for by latitude and longitude than by national percentage of Finno-Ugrians and type 0 blood: a rebuttal of Lester and Kondrichin (2004). Percept Mot Skills 99: 1243–1250PubMedCrossRefGoogle Scholar
  14. Marušič A (2005) History and geography of suicide: could genetic risk factors account for the variation in suicide rates? [editorial] Am J Med Genet C: Semin Med Genet 133C: 43–47CrossRefGoogle Scholar
  15. Voracek M (2006) Ancestry, genes, and suicide: a test of the Finno-Ugrian Suicide Hypothesis in the United States. Percept Mot Skills 103: 543–550PubMedCrossRefGoogle Scholar
  16. Voracek M, Loibl LM, Kandrychyn S (2007) Testing the Finno-Ugrian Suicide Hypothesis: replication and refinement with regional suicide data from Eastern Europe. Percept Mot Skills 104: 985–994PubMedGoogle Scholar
  17. Voracek M, Marušič A (2006) Testing the Finno-Ugrian Suicide Hypothesis: geographical variation of elderly suicide rates across Europe. [Ms. submitted for publication]Google Scholar
  18. Ferrada-Noli M (1997) A cross-cultural breakdown of Swedish suicide. Acta Psychiatr Scand 96: 108–116PubMedGoogle Scholar
  19. Hjern A, Allebeck P (2002) Suicide in first- and secondgeneration immigrants in Sweden: a comparative study. Soc Psychiatry Psychiatr Epidemiol 37: 423–429PubMedCrossRefGoogle Scholar
  20. Marušič A, Perman M, Zorko M, Kravanja M (2006) Investigating surnames of males who committed suicide in a patrilineal society [abstract]. Psychiatr Danub 18 [Suppl 1]: 140Google Scholar
  21. Voracek M, Sonneck G (2007) Surname study of suicide in Austria: differences in regional suicide rates correspond to the genetic structure of the population. Wien Klin Wochenschr 119: 355–360PubMedCrossRefGoogle Scholar
  22. Tsuang MT (1977) Genetic factors in suicide. Dis Nerv Syst 38: 498–501PubMedGoogle Scholar
  23. Lester D (1986) Genetics, twin studies and suicide. Suicide Life Threat Behav 16: 274–285PubMedGoogle Scholar
  24. Roy A (1992) Are there genetic factors in suicide? Int Rev Psychiatry 4: 169–175Google Scholar
  25. Roy A (1993) Genetic and biologic risk factors for suicide in depressive disorders. Psychiatric Q 64: 345–358CrossRefGoogle Scholar
  26. Roy A, Rylander G, Sarchiapone M (1997) Genetics of suicide: family studies and molecular genetics. Ann NY Acad Sci 836: 135–157PubMedCrossRefGoogle Scholar
  27. Roy A, Nielsen D, Rylander G, Sarchiapone M, Segal N (1999) Genetics of suicide in depression. J Clin Psychiatry 60 [Suppl 2]: 12–17PubMedGoogle Scholar
  28. Roy A, Nielsen D, Rylander G, Sarchiapone M (2000) The genetics of suicidal behaviour. In: Hawton K, van Heeringen K (eds) The international handbook of suicide and attempted suicide. John Wiley, Chichester, pp 209–221Google Scholar
  29. Zalsman G, Frisch A, Apter A, Weizman A (2002) Genetics of suicidal behavior: candidate association genetic approach. Isr J Psychiatry Relat Sci 39: 252–261PubMedGoogle Scholar
  30. Haberlandt W (1965) Der Suizid als genetisches Problem (Zwillings- und Familienanalyse) [Suicide from the view of genetics: twin and family analyses]. Anthropolog Anz 29: 65–89Google Scholar
  31. Haberlandt WF (1967) Aportación a la genética del suicidio: datos en gemelos y hallazgos familiares [Contribution to the genetics of suicide: data in twins and familial findings]. Folia Clin Int Barc 17: 319–322PubMedGoogle Scholar
  32. Lester D (2002) Twin studies of suicidal behavior. Arch Suicide Res 6: 383–389CrossRefGoogle Scholar
  33. Voracek M, Formann AK, Fülöp G, Sonneck G (2003) Suicide and general elections in Austria: do preceding regional suicide rate differentials foreshadow subsequent voting behavior swings? J Affect Disord 74: 257–266PubMedCrossRefGoogle Scholar
  34. Voracek M (2004) National intelligence and suicide rate: an ecological study of 85 countries. Pers Individ Dif 37: 543–553CrossRefGoogle Scholar
  35. Voracek M (2006) Smart and suicidal? The social ecology of intelligence and suicide in Austria. Death Stud 30: 471–485PubMedCrossRefGoogle Scholar
  36. Dervic K, Friedrich E, Oquendo MA, Voracek M, Friedrich MH, Sonneck G (2006) Suicide in Austrian children and young adolescents ages 14 and younger. Eur Child Adolesc Psychiatry 15: 427–434PubMedCrossRefGoogle Scholar
  37. Dervic K, Friedrich E, Prosquill D, Kapusta ND, Lenz G, Sonneck G, Friedrich MH (2006) Suicide among Viennese minors, 1946–2002. Wien Klin Wochenschr 118: 152–159PubMedCrossRefGoogle Scholar
  38. Etzersdorfer E, Kapusta ND, Sonneck G (2006) Suicide by shooting is correlated to rate of gun licenses in Austrian counties. Wien Klin Wochenschr 118: 464–468PubMedCrossRefGoogle Scholar
  39. Etzersdorfer E, Voracek M, Kapusta N, Sonneck G (2005) Epidemiology of suicide in Austria 1990–2000: general decrease, but increased suicide risk for old men. Wien Klin Wochenschr 117: 31–35PubMedCrossRefGoogle Scholar
  40. Friedrich MH (2006) Suizid im Kindes- und Jugendalter [Suicide in children and adolescents]. Wien Klin Wochenschr 118: 131–133PubMedCrossRefGoogle Scholar
  41. Leenaars AA (2006) Suicide by shooting and gun ownership (licenses) in Austria: would gun restriction help? Wien Klin Wochenschr 118: 439–441PubMedCrossRefGoogle Scholar
  42. Ritter K, Stompe T, Voracek M, Etzersdorfer E (2002) Suicide risk-related knowledge and attitudes of general practitioners. Wien Klin Wochenschr 114: 685–690PubMedGoogle Scholar
  43. Allen G, Harvald B, Shields J (1967) Measures of twin concordance. Acta Genet Stat Med 17: 475–481PubMedGoogle Scholar
  44. Smith C (1974) Concordance in twins: methods and interpretation. Am J Hum Genet 26: 454–466PubMedGoogle Scholar
  45. Mellon CD (1996) Hereditary madness: the evolution of psychiatric genetic thought. Genetics Heritage Press, Placitas (NM), pp 48–49, 96, 120–121Google Scholar
  46. Cho H, Guo G, Iritani BJ, Hallfors DD (2006) Genetic contribution to suicidal behaviors and associated risk factors among adolescents in the U.S. Prev Sci 7: 303–311PubMedCrossRefGoogle Scholar
  47. Holzinger KJ (1929) The relative effect of nature and nurture influences on twin differences. J Educ Psychol 20: 241–248CrossRefGoogle Scholar
  48. Borenstein M, Hedges L, Higgins J, Rothstein H (2005) Comprehensive Meta-Analysis, Version 2 [computer software]. Biostat, Englewood (NJ)Google Scholar
  49. Rush B (1812) Medical inquiries and observations, upon the diseases of the mind. Kimber, PhiladelphiaGoogle Scholar
  50. Loewenberg RD (1941) Suicide in twins: a historical note. J Nerv Ment Dis 93: 182–184CrossRefGoogle Scholar
  51. Baume (1863) Singulier cas de folie suicide chez deux frères jumeaux: coïncidence bizarre [A unique case of suicidal insanity among two twin brothers: a bizarre coincidence]. Ann Med Psychol Paris: 312–313Google Scholar
  52. Smith P (1912) Psychoses occurring in twins. NY Med J 12: 1268–1272Google Scholar
  53. Soukhanoff S (1912) De la soi-disant folie gémellaire [About the so-called twin insanity]. Revue de Psychiatrie et de Psychologie Expérimentale 16: 486–492Google Scholar
  54. Soukhanoff S (1900) Sur la folie gémellaire [About twin insanity]. Ann Med Psychol 2: 214–231Google Scholar
  55. Le Gras AM (1932) Psychose en criminaliteit bij tweelingen [Psychosis and criminality in twins]. Kemink, Utrecht (The Netherlands)Google Scholar
  56. Le Gras AM (1933) Psychose und Kriminalität bei Zwillingen [Psychosis and criminality in twins]. Zeitschrift für die gesamte Neurologie und Psychiatrie 144: 198–221Google Scholar
  57. Menninger KA (1938) Man against himself. George G. Harrap, LondonGoogle Scholar
  58. Hanhart E (1968/69) Zur Frage der Beteiligung genetischer Faktoren bei Selbstmorden anhand von temporären Häufungen familiärer Suizide in Schweizer Isolaten [On the question of a contribution of genetic factors in suicide based on temporary increases in the rate of familial suicides in Swiss isolates]. Arch Julius Klaus Stift Vererbungsforsch Sozialanthropol Rassenhyg 43–44: 305–376Google Scholar
  59. Gedda L (1951) Studio dei gemelli [Twin studies]. Edizioni Orizzonte Medico, RomaGoogle Scholar
  60. Vogt A, Wagner H, Richner H, Meyer G (1939) Das Senium bei eineiigen und zweieiigen Zwillingen: Die Erbentstehung bisher exogen und durch "Abnützung" erklärter Altersleiden [Old age in monozygotic and dizygotic twins: on the inheritance of late-onset diseases previously explained environmentally and through depletion]. Arch Julius Klaus Stift Vererbungsforsch Sozialanthropol Rassenhyg 14: 475–597Google Scholar
  61. von Verschuer O (1954) Wirksame Faktoren im Leben des Menschen: Beobachtungen an ein- und zweieiigen Zwillingen durch 25 Jahre [Influential factors over the human life cycle: observations on monozygotic and dizygotic twins over 25 years]. Franz Steiner, Wiesbaden (Germany)Google Scholar
  62. Koch G (1957) Ergebnisse aus der Nachuntersuchung der Berliner Zwillingsserie nach 20–25 Jahren (vorläufige Ergebnisse) [Follow-up results from the Berlin twin series after 20–25 years (preliminary findings)]. Acta Genet 7: 47–52PubMedGoogle Scholar
  63. Swanson DW (1960) Suicide in identical twins. Am J Psychiatry 115: 934–935Google Scholar
  64. Wilson IC, Reece JC (1964) Simultaneous death in schizophrenic twins. Arch Gen Psychiatry 11: 377–384PubMedGoogle Scholar
  65. Berger H (1964) Manisch-depressive Psychosen bei eineiigen Zwillingen [Manic-depressive psychoses in monozygotic twins]. Medical dissertation, University of Munich (Germany)Google Scholar
  66. Blath R, McClure J, Wetzel R (1973) Familial factors in suicide. Dis Nerv Syst 34: 90–93PubMedGoogle Scholar
  67. Zaw KM (1981) A suicidal family. Br J Psychiatry 139: 68–69PubMedGoogle Scholar
  68. Kallmann FJ, Anastasio M (1946) Twin studies on the psychopathology of suicide. J Hered 37: 171–180Google Scholar
  69. Kallmann FJ, Anastasio MM (1947) Twin studies on the psychopathology of suicide. J Nerv Ment Dis 105: 40–55CrossRefPubMedGoogle Scholar
  70. Kallmann FJ, De Porte J, De Porte E, Feingold L (1949) Suicide in twins and only children. Am J Hum Genet 1: 113–126PubMedGoogle Scholar
  71. Kallmann FJ (1953) Heredity in health and mental disease: principles of psychiatric genetics in the light of comparative twin studies. Norton, New YorkGoogle Scholar
  72. Lester D (1968) Note on the inheritance of suicide. Psychol Rep 22: 320PubMedGoogle Scholar
  73. Bertelsen A, Harvald B, Hauge M (1977) A Danish twin study of manic-depressive disorders. Br J Psychiatry 130: 330–351PubMedGoogle Scholar
  74. Harvald B, Hauge M (1965) Hereditary factors elucidated by twin studies. In: Neel JV, Shaw MW, Schull WJ (eds) Genetics and the epidemiology of chronic disease. U.S. Department of Health, Education, and Welfare, Washington (DC), pp 61–76Google Scholar
  75. Hauge M, Harvald B, Fischer M, Gotlieb-Jensen K, Juel-Nielsen N, Raebild I, et al (1968) The Danish twin register. Acta Genet Med Gemellol Roma 17: 315–331PubMedGoogle Scholar
  76. Juel-Nielsen N, Videbech T (1970) A twin study of suicide. Acta Genet Med Gemellol Roma 19: 307–310PubMedGoogle Scholar
  77. Juel-Nielsen N (1979) Suicide risk in manic-depressive disorders. In: Schou M, Strömgren E (eds) Origin, prevention and treatment of affective disorders. Academic Press, London, pp 269–276Google Scholar
  78. Roy A, Segal NL, Centerwall BS, Robinette CD (1991) Suicide in twins. Arch Gen Psychiatry 48: 29–32PubMedGoogle Scholar
  79. Segal NL, Bouchard TJ (1993) Grief intensity following the loss of a twin and other relatives: test of kinship genetic hypotheses. Hum Biol 65: 87–105PubMedGoogle Scholar
  80. Segal NL, Wilson SM, Bouchard TJ, Gitlin D (1995) Comparative grief experiences of bereaved twins and other bereaved relatives. Pers Individ Dif 18: 511–524CrossRefGoogle Scholar
  81. McGuffin P, Marušič A, Farmer A (2001) What can psychiatric genetics offer suicidology? Crisis 22: 61–65PubMedGoogle Scholar
  82. Roy A, Segal NL (2001) Suicidal behavior in twins: a replication. J Affect Disord 66: 71–74PubMedCrossRefGoogle Scholar
  83. Kaprio J, Romanov K, Lönnqvist J, Koskenvuo M (1995) Suicide in twins: the Finnish twin cohort study [abstract]. Psychiatr Genet 5: S102CrossRefGoogle Scholar
  84. Statham DJ, Heath AC, Madden PAF, Bucholz KK, Bierut L, Dinwiddie SH, et al (1998) Suicidal behavior: an epidemiological and genetic study. Psychol Med 28: 839–855PubMedCrossRefGoogle Scholar
  85. Fu Q, Heath AC, Bucholz KK, Nelson EC, Glowinski AL, Goldberg J, et al (2002) A twin study of genetic and environmental influences on suicidality in men. Psychol Med 32: 11–24PubMedCrossRefGoogle Scholar
  86. Glowinski AL, Bucholz KK, Nelson EC, Fu Q, Madden PA, Reich W, Health AC (2001) Suicide attempts in an adolescent female twin sample. J Am Acad Child Adolesc Psychiatry 40: 1300–1307PubMedCrossRefGoogle Scholar
  87. Roy A, Segal NL, Sarchiapone M (1995) Attempted suicide among living co-twins of twin suicide victims. Am J Psychiatry 152: 1075–1076PubMedGoogle Scholar
  88. Roy A, Rylander G, Forslund K, Asberg M, Mazzanti CM, Goldman D, Nielsen DA (2001) Excess tryptophan hydroxylase 17 779C allele in surviving cotwins of monozygotic twin suicide victims. Neuropsychobiology 43: 233–236PubMedCrossRefGoogle Scholar
  89. Voracek M, Tran US (2007) Dietary tryptophan intake and suicide rate in industrialized nations. J Affect Disord 98: 259–262PubMedCrossRefGoogle Scholar
  90. Segal NL, Roy A (1995) Suicide attempts in twins whose co-twins deaths were non-suicides. Pers Individ Dif 19: 937–940CrossRefGoogle Scholar
  91. Pompili M, Galeandro PM, Lester D, Tatarelli R (2006) Suicidal behavior in surviving co-twins. Twin Res Hum Genet 9: 642–645PubMedCrossRefGoogle Scholar
  92. Segal N, Roy A (2001) Suicidal attempts and ideation in twins whose co-twin deaths were non-suicides: replication and extension. Pers Individ Dif 31: 445–452CrossRefGoogle Scholar
  93. Newman HH, Freeman FH, Holzinger KJ (1937) Twins: a study of heredity and environment. University of Chicago Press, ChicagoGoogle Scholar
  94. Bouchard TJ, Lykken DT, McGue M, Segal NL, Tellegen A (1990) Sources of human psychological differences: the Minnesota Study of Twins Reared Apart. Science 250: 223–228PubMedCrossRefGoogle Scholar
  95. Shields J (1962) Monozygotic twins, brought up apart and brought up together: an investigation into the genetic and environmental causes of variation in personality. Oxford University Press, LondonGoogle Scholar
  96. Juel-Nielsen N (1965) Individual and environment: a psychiatric-psychological investigation of monozygotic twins reared apart. Acta Psychiatr Scand [Suppl 183]: 1–158, 1–292Google Scholar
  97. Pedersen NL, Plomin R, Nesselroade JR, McClearn GE (1992) A quantitative genetic analysis of cognitive abilities during the second half of the life span. Psychol Sci 3: 346–353CrossRefGoogle Scholar
  98. Langinvainio H, Koskenvuo M, Kaprio J, Sistonen P (1984) Finnish twins reared apart. II: validation of zygosity, environmental dissimilarity and weight and height. Acta Genet Med Gemellol Roma 33: 251–258PubMedGoogle Scholar
  99. Burt C (1966) Genetic determination of differences in intelligence: a study of monozygotic twins reared together and apart. Br J Psychol 57: 137–153 PubMedGoogle Scholar
  100. Hearnshaw LS (1979) Cyril Burt: psychologist. Cornell University Press, Ithaca (NY)Google Scholar
  101. Joynson RB (1989) The Burt affair. Routledge, LondonGoogle Scholar
  102. Fletcher R (1991) Science, ideology, and the media: the Cyril Burt scandal. Transaction Publishers, New Brunswick (NJ)Google Scholar
  103. Rushton JP (2002) New evidence on Sir Cyril Burt: his 1964 speech to the Association of Educational Psychologists. Intelligence 30: 555–567Google Scholar
  104. Burbridge D (2006) Burt's twins: a question of numbers. J Hist Behav Sci 42: 335–352PubMedCrossRefGoogle Scholar
  105. Spaeth J (1860) Studien über Zwillinge [Twin studies]. Zeitschrift der Wiener Gesellschaft der Ärzte 16: 225–231, 241–244Google Scholar
  106. Spaeth J (1862) Studies regarding twins. Edinburgh Med J 7: 841–849Google Scholar
  107. Kleinwächter L (1871) Die Lehre von den Zwillingen [Twin studies]. Haerpfer, PragueGoogle Scholar
  108. Galton F (1875) The history of twins, as a criterion of the relative powers of nature and nurture. J Anthropol Inst 5: 391–406Google Scholar
  109. Siemens HW (1924) Die Zwillingspathologie: ihre Bedeutung, ihre Methodik, ihre bisherigen Ergebnisse [The twin pathology: its relevance, method, and results so far]. Springer, BerlinGoogle Scholar
  110. Holland T, Gosden C (1990) A balanced chromosomal translocation partially co-segregating with psychotic illness in a family. Psychiatry Res 32: 1–8PubMedCrossRefGoogle Scholar
  111. Weinberg W (1927) Mathematische Grundlagen der Probandenmethode [Mathematical foundations of the proband method]. Z Indukt Abstamm Vererbungsl 48: 179–228CrossRefGoogle Scholar
  112. Strömgren E (1935) Zum Ersatz des Weinbergschen "abgekürzten Verfahrens": zugleich ein Beitrag zur Frage von der Erblichkeit des Erkrankungsalters bei der Schizophrenie [On the substitution of Weinberg's abbreviated procedure: concomitantly a contribution to the question of age-of-onset heritability in schizophrenia]. Zeitschrift für die gesamte Neurologie und Psychiatrie 153: 784–797Google Scholar
  113. Slater E (1953) Psychotic and neurotic illnesses in twins. Her Majesty's Stationary Office, LondonGoogle Scholar
  114. Tomassini C, Juel K, Holm NV, Skytthe A, Christensen K (2003) Risk of suicide in twins: 51 year follow up study. Br Med J 327: 373–374CrossRefGoogle Scholar
  115. Voracek M (2003) Risk of suicide in twins: intelligence of twins and singletons may explain risk [letter]. Br Med J 327: 1168CrossRefGoogle Scholar
  116. Bostwick JM, Pankratz VS (2000) Affective disorders and suicide risk: a reexamination. Am J Psychiatry 157: 1925–1932PubMedCrossRefGoogle Scholar
  117. Tariverdian G, Buselmaier W (2004) Humangenetik [Human genetics], 3rd, rev. edn. Springer, Berlin, p 371Google Scholar
  118. Haberlandt WF (2003) Rückblick eines Wissenschaftlers – Bekenntnis eines Zeitzeugen: 1921–2001 [Memoirs of a scientist – confessions of a contemporary witness: 1921–2001]. VGB-Verlagsgesellschaft, Inning am Ammersee (Germany)Google Scholar

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Authors and Affiliations

  1. 1.Department of Basic Psychological Research, School of PsychologyUniversity of ViennaViennaAustria

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