Sample Size Requirements

Abstract

Sample size requirements in the context of linkage analysis between a trait and genetic markers refer to the calculation of the sample size required for a linkage study to guarantee a certain power of the study against an assumed inheritance model. The power against an assumed inheritance model is the probability of correctly declaring a linkage when in fact the assumed inheritance model is true and the trait and marker loci are linked.

Keywords: power; inheritance model; parametric linkage analysis; affected sibling pair test; transmission/disequilibrium test

References

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Further Reading

Chen WM and Deng HW (2001) A general and accurate approach for computing the statistical power of the transmission disequilibrium test for complex disease genes. Genetic Epidemiology 21: 53–67.

Holmans P (2001) Nonparametric linkage. In: Balding DJ, Bishop M and Cannings C (eds.) Handbook of Statistical Genetics, pp. 541–563. Chichester, UK: Wiley.

Holmans P and Clayton D (1995) Efficiency of typing unaffected relatives in an affected‐sib‐pair linkage study with single‐locus and multiple tightly linked markers. American Journal of Human Genetics 57: 1221–1232.

Krawczak M (2001) ASP – a simulation‐based power calculator for genetic linkage studies of qualitative traits, using sib‐pairs. Human Genetics 109: 675–677.

Risch N (2000) Searching for genetic determinants in the new millennium. Nature 405: 847–856.

Thompson EA (2001) Linkage analysis. In: Balding DJ, Bishop M and Cannings C (eds.) Handbook of Statistical Genetics, pp. 541–563. Chichester, UK: Wiley.

Weeks DE and Lathrop GM (1995) Polygenic disease: methods for mapping complex disease traits. Trends in Genetics 11: 513–519.

Web Links

SAS macro to compute power approximations for the TDT http://www.uni‐bonn.de/∼umt70e/soft.htm

SIMLINK program www.sph.umich.edu/statgen/boehnke/simlink.html

SIMULATE program ftp://linkage.rockefeller.edu/software/simulate

SLINK program ftp://linkage.rockefeller.edu/software/slink

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How to Cite close
Knapp, Michael(Jan 2006) Sample Size Requirements. In: eLS. John Wiley & Sons Ltd, Chichester. http://www.els.net [doi: 10.1038/npg.els.0005436]