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Appraisal of Parental Bias in Twin Studies. Ascribed Zygosity and IQ Differences in Twins

Published online by Cambridge University Press:  01 August 2014

Adam P. Matheny Jr.*
Affiliation:
The Louisville Twin Study, University of Louisville School of Medicine, Kentucky
*
The Louisville Twin Study, PO Box 35260, University of Louisville School of Medicine, KY 40232

Abstract

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A criticism of twin studies has been that the difference between the behavioral similarities of identical and fraternal twins is largely created by parental influences based on their perception of the twins' zygosity. This issue is examined for differences in the IQ scores found within pairs classified by parents and bloodtyping. The systematic differences in IQ scores could be attributed to zygosity classified by bloodtyping rather than by parental belief. The available evidence indicates that the twin method is still appropriate for human behavior genetics.

Type
Research Article
Copyright
Copyright © The International Society for Twin Studies 1979

References

REFERENCES

1.Cohen, DJ, Dibble, E, Grawe, JM 1977: Parental style: Mothers' and fathers' perceptions of their relations with twin children. Arch Gen Psychiatry 34:445451.CrossRefGoogle ScholarPubMed
2.Cohen, DJ, Dibble, E, Grawe, JM, Pollin, W 1973: Separating identical from fraternal twins. Arch Gen Psychiatry 29:465469.CrossRefGoogle ScholarPubMed
3.Kamin, LJ (1974): “The Science and Politics of IQ.” Potomac, Maryland: Lawrence Erlbaum.Google Scholar
4.Loehlin, JC, Nichols, RC (1976): “Heredity, Environment, and Personality.” Austin, Texas: University of Texas Press.Google Scholar
5.Lytton, H (1977): Do parents create, or respond to, differences in twins? Psychologist 13:456459.Google Scholar
6.Munsinger, H, Douglass, A 1976: The syntactic abilities of identical twins, fraternal twins, and their siblings. Child Dev 47:4050.CrossRefGoogle Scholar
7.Scarr, S 1968: Environmental bias in twin studies. Eugen Q 15:3440.CrossRefGoogle ScholarPubMed
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, 1965.Google Scholar
9.Wilson, RS 1974: Twins: Mental development in the preschool years. Dev Psychol 10:580588.CrossRefGoogle Scholar
10.Wilson, RS (1977): Twins and siblings: Concordance for school-age mental development. Child Dev 48:211216.CrossRefGoogle Scholar