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Cotwin Closeness in Monozygotic and Dizygotic Twins: A Biasing Factor in IQ Heritability Analysis?

Published online by Cambridge University Press:  01 August 2014

K. Tambs ,
J. M. Sundet  and
K. Berg
K. Tambs*
Affiliation:
Institute of Psychology
J. M. Sundet
Affiliation:
Institute of Psychology
K. Berg
Affiliation:
Institute of Medical Genetics, University of Oslo
*
Institute of Psychology, Box 1094, Blindern, Oslo 3, Norway

Abstract

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For 98 pairs of MZ twins, four measures indicating degree of cotwin closeness were correlated with absolute differences between IQ scores within pairs. In two different twin samples (40 MZ vs 40 DZ pairs and 169 MZ vs 174 DZ pairs, respectively), means and standard deviations in the closeness variables were obtained for MZ and DZ pairs. Whereas MZ cotwins were clearly closer than DZ cotwins, the relation between cotwin closeness and similarity in IQ seemed rather weak and ambiguous. “Years lived together in childhood home” were positively related to similarity in IQ (P < 0.01), whereas subjective feeling of closeness in contact tended to be negatively related to similarity in IQ.

Keywords

IQ and environmentTwin methodEnvironmental similarity in twins
Type
Review Article
Information
Acta geneticae medicae et gemellologiae: twin research , Volume 34 , Issue 1-2 , April 1985 , pp. 33 - 39
Copyright
Copyright © The International Society for Twin Studies 1985

References

REFERENCES

1. Engvik, H (1978): Kjonnsfoiskjeller i WAIS. Paper at Institute of Psychology, University of Oslo.Google Scholar
2. Hogarth, R (1974): Monozygotic and dizygotic twins reared together: Sensitivity of heritability estimates. Br J Math Stat Psychol 27, part I.Google Scholar
3. Jencks, C, Brown, M (1977): Genes and social stratification: A methodological exploration with illustrative data. In Taubman, P (ed): Kinometrics: Determinants of Socioeconomic Success Within and Between Families. Amsterdam: North Holland.Google Scholar
4. Koch, HD (1976): Twins and Twin Relations. Chicago: University of Chicago Press.Google Scholar
5. Loehlin, JC, Nichols, RC (1976): Heredity, Environment and Personality. A Study of 850 Sets of Twins. Austin: University of Texas Press.Google Scholar
6. Magnus, P, Berg, K, Nance, WE (1983): Predicting zygosity in twins born 1915-1960. Clin Genet 24:103–112.Google Scholar
7. Matheny, AP, Wilson, RS, Brown, DA (1976): Relations between twins' similarity of appearence and behavioral similarity: Testing an assumption. Behav Genet 6:343–350.Google Scholar
8. Smith, RT (1965): A comparison of socioenvironmental factors in monozygotic and dizygotic twins testing an assumption. In Vandenberg, SG (ed): Methods and Goals in Human Behavior Genetics. New York: Academic Press.Google Scholar