Behavior Genetics

, Volume 39, Issue 5, pp 571–579 | Cite as

Novel Sib Pair Selection Strategy Increases Power in Quantitative Association Analysis

  • Johnny S. H. Kwan
  • Stacey S. Cherny
  • Annie W. C. Kung
  • Pak C. Sham
Original Research
First Online:
Received:
Accepted:

Abstract

Quantitative-trait association studies have been widely used in search for genetic loci for complex traits in recent years. Yet, fiscal constraints still prohibit many on-going research projects from recruiting a large number of individuals for genotyping to reach a desired level of statistical power. Accordingly, in this article, we describe a novel sib pair sampling strategy for genotyping in QTL association studies. With the use of phenotypic scores (and IBD allele-sharing probabilities if available), the genetic effect of a biallelic additive trait locus can be properly modelled within the maximum-likelihood variance components framework proposed by Fulker et al. (Am J Hum Genet 64(1):259–267, 1999) and sib pairs can be rank-ordered by use of informativeness indices. The performance of our method was investigated using simulation. The power of our approach was shown to be higher when compared with other phenotypic selection schemes. An R-script implementing all the selection approaches (including the traditional phenotype-based ones) used in the simulation is available at http://statgen.hku.hk/jshkwan.

Keywords

Quantitative trait association Sample selection Linkage disequilibrium analysis 
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Notes

Acknowledgments

This work was supported by grants HKU 7674/07M (A.W.C.K) and HKU 7669/06M (P.C.S) from the Research Grants Council of Hong Kong and grant EY-12562 (S.S.C, P.C.S) from the National Institutes of Health (USA).

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Copyright information

© Springer Science+Business Media, LLC 2009

Authors and Affiliations

  • Johnny S. H. Kwan
    • 1
    • 2
  • Stacey S. Cherny
    • 1
    • 2
    • 3
  • Annie W. C. Kung
    • 4
  • Pak C. Sham
    • 1
    • 2
  1. 1.Department of PsychiatryUniversity of Hong KongHong KongChina
  2. 2.Genome Research CentreUniversity of Hong KongHong KongChina
  3. 3.The State Key Laboratory of Brain and Cognitive SciencesUniversity of Hong KongHong KongChina
  4. 4.Department of MedicineUniversity of Hong KongHong KongChina

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