BMC Bioinformatics

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Open Access Software

Computing power of quantitative trait locus association mapping for haploid loci

Derek Gordon1* and Andrew R Zinn2

Author Affiliations

1 Department of Genetics, Rutgers University, 145 Bevier Road, Piscataway, NJ 08854, USA

2 McDermott Center for Human Growth and Development, University of Texas Southwestern Medical School, 5323 Harry Hines Blvd, Dallas, TX 75390-8591, USA

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BMC Bioinformatics 2009, 10:261 doi:10.1186/1471-2105-10-261

Published: 23 August 2009

Abstract

Background

Statistical power calculations are a critical part of any study design for gene mapping. Most calculations assume that the locus of interest is biallelic. However, there are common situations in human genetics such as X-linked loci in males where the locus is haploid. The purpose of this work is to mathematically derive the biometric model for haploid loci, and to compute power for QTL mapping when the loci are haploid.

Results

We have derived the biometric model for power calculations for haploid loci and have developed software to perform these calculations. We have verified our calculations with independent mathematical methods.

Conclusion

Our results fill a need in power calculations for QTL mapping studies. Furthermore, failure to appropriately model haploid loci may cause underestimation of power.