Hostname: page-component-78c5997874-m6dg7 Total loading time: 0 Render date: 2024-11-10T15:39:03.163Z Has data issue: false hasContentIssue false
  • English
  • Français

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

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

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

REFERENCES

1.Elston, RC, Stewart, J (1971. A general model for the genetic analysis of pedigree data. Hum Hered 21:523–542.CrossRefGoogle ScholarPubMed
2.Fishman, PM, Reich, T, Suarez, B, James, JW (1978. A note on the essential parameters of the two-allele autosomal locus model. Am J Hum Genet 30:283–292.Google ScholarPubMed
3.Huizinga, J, Heiden, JA (1957. The percentages of concordance in twins and mode of inheritance. Acta Genet Med Gemellol 6:437–450.Google Scholar
4.James, JW (1971. Frequency in relatives for an all-or-none trait. Ann Hum Genet 35:47–49.Google Scholar
5.Kempthorne, O (1957): “An Introduction to Genetic Statistics.” New York: John Wiley.Google Scholar
6.Reich, T, James, JW, Morris, CA (1972. The use of multiple thresholds in determining the mode of transmission of semi-continuous traits. Ann Hum Genet 36:163–184.Google Scholar
7.Suarez, B (1978. The affected sib pair IBD distribution for HLA-linked disease susceptibility genes. Tissue Antigens 12:87–93.CrossRefGoogle ScholarPubMed
8.Suarez, BK, Reich, T, Trost, J (1976): Limits of the general two-allele single locus model with incomplete penetrance. Ann Hum Genet 40:231–244.Google Scholar
9.Suarez, B, Fishman, PM, Reich, T (1977. Estimating the parameters of the incompletely penetrant single locus model using multiple populations. Hum Hered 27:336–351.Google Scholar
10.Suarez, B, Rice, J, Reich, T (1978. The generalized sib pair IBD distribution: Its use in the detection of linkage. Ann Hum Genet 42:87–94.CrossRefGoogle ScholarPubMed