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Conditional Concordance in Monozygotic Twins

Published online by Cambridge University Press:  01 August 2014

Brian Suarez
Brian Suarez*
Affiliation:
Department of Psychiatry, Washington University School of Medicine, The Jewish Hospital of St. Louis, Missouri
*
Department of Psychiatry, The Jewish Hospital, PO Box 14109, St. Louis, MO 63178, USA

Abstract

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Twin concordance rates are usually reported without reference to the number of parents affected, apparently because the simple demonstration that monozygotic (MZ) twins are more concordant than are dizygotic (DZ) twins is the goal of most twin studies. Depending on the underlying mechanism, however, twin concordance rates can vary widely when conditioned on the number of parents affected. For the generalized single-locus model it is shown that conditional concordance rates in monozygotic twins, along with an estimate of the disorder's prevalence in the population, uniquely specify the underlying parameters of this important model. Knowledge of the exact parameter set is essential for competent genetic counseling.

Keywords

Twin concordance ratesConditional concordanceSingle-locus modelGenetic counseling
Type
Research Article
Information
Acta geneticae medicae et gemellologiae: twin research , Volume 29 , Issue 2 , April 1980 , pp. 137 - 142
Copyright
Copyright © The International Society for Twin Studies 1980

References

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