跳至主要内容

Implicit Hypotheses Are Hidden Power Droppers in Family-Based Association Studies of Secondary Outcomes

Read  full  paper  at:
http://www.scirp.org/journal/PaperInformation.aspx?PaperID=53677#.VM8uZSzQrzE

ABSTRACT
Family-based tests of association between a genetic marker and a disease constitute a common design to dissect the genetic architecture of complex traits. The FBAT software is one of the most popular tools to perform such studies. However, researchers are also often interested in the genetic contribution to a more specific manifestation of the phenotype (e.g. severe vs. non-severe form) known as a secondary outcome. Here, what we demonstrate is the limited power of the classical formulation of the FBAT statistic to detect the effect of genetic variants that influence a secondary outcome, in particular when these variants also impact on the onset of the disease, the primary outcome. We prove that this loss of power is driven by an implicit hypothesis, and we propose a derivation of the original FBAT statistic, free from this implicit hypothesis. Finally, we demonstrate analytically that our new statistic is robust and more powerful than FBAT for the detection of association between a genetic variant and a secondary outcome.
 
Cite this paper
Gaschignard, J. , Vincent, Q. , Jaïs, J. , Cobat, A. and Alcaïs, A. (2015) Implicit Hypotheses Are Hidden Power Droppers in Family-Based Association Studies of Secondary Outcomes. Open Journal of Statistics, 5, 35-45. doi: 10.4236/ojs.2015.51005.
 
References
[1]Laird, N.M. and Lange, C. (2006) Family-Based Designs in the Age of Large-Scale Gene-Association Studies. Nature Reviews Genetics, 7, 385-394.
http://dx.doi.org/10.1038/nrg1839
 
[2]Chen, W.M. and Abecasis, G.R. (2007) Family-Based Association Tests for Genomewide Association Scans. American Journal of Human Genetics, 81, 913-926.
http://dx.doi.org/10.1086/521580
 
[3]Burdick, J.T., Chen, W.M., Abecasis, G.R. and Cheung, V.G. (2006) In Silico Methods for Inferring Genotypes in Pedigrees. Nature Genetics, 38, 1002-1004.
http://dx.doi.org/10.1038/ng1863
 
[4]Vincent, Q., Alcais, A., Alter, A., Schurr, E. and Abel, L. (2006) Quantifying Genomic Imprinting in the Presence of Linkage. Biometrics, 62, 1071-1080.
http://dx.doi.org/10.1111/j.1541-0420.2006.00610.x
 
[5]Spielman, R.S., McGinnis, R.E. and Ewens, W.J. (1993) Transmission Test for Linkage Disequilibrium: The Insulin Gene Region and Insulin-Dependent Diabetes Mellitus (IDDM). American Journal of Human Genetics, 52, 506-516.
 
[6]Laird, N.M., Horvath, S. and Xu, X. (2000) Implementing a Unified Approach to Family-Based Tests of Association. Genetic Epidemiology, 19, S36-S42.
http://dx.doi.org/10.1002/1098-2272(2000)19:1+<::AID-GEPI6>3.0.CO;2-M
 
[7]Rabinowitz, D. and Laird, N. (2000) A Unified Approach to Adjusting Association Tests for Population Admixture with Arbitrary Pedigree Structure and Arbitrary Missing Marker Information. Human Heredity, 50, 211-223.
http://dx.doi.org/10.1159/000022918
 
[8]Lange, C. and Laird, N.M. (2002) Power Calculations for a General Class of Family-Based Association Tests: Dichotomous Traits. American Journal of Human Genetics, 71, 575-584.
http://dx.doi.org/10.1086/342406
 
[9]Mira, M.T., Alcais, A., Van Thuc, N., Moraes, M.O., Di Flumeri, C., Hong Thai, V., Chi Phuong, M., Thu Huong, N., Ngoc Ba, N., Xuan Khoa, P., et al. (2004) Susceptibility to Leprosy Is Associated with PARK2 and PACRG. Nature, 427, 636-640.
http://dx.doi.org/10.1038/nature02326
 
[10]Cobat, A., Gallant, C.J., Simkin, L., Black, G.F., Stanley, K., Hughes, J., Doherty, T.M., Hanekom, W.A., Eley, B., Jais, J.P., et al. (2009) Two Loci Control Tuberculin Skin Test Reactivity in an Area Hyperendemic for Tuberculosis. Journal of Experimental Medicine, 206, 2583-2591.
http://dx.doi.org/10.1084/jem.20090892
 
[11]Knapp, M. (1999) The Transmission/Disequilibrium Test and Parental-Genotype Reconstruction: The Reconstruction-Combined Transmission/Disequilibrium Test. American Journal of Human Genetics, 64, 861-870.
http://dx.doi.org/10.1086/302285                                                                                 eww150202lx

评论

此博客中的热门博文

Does Immigration Promote the Investment of the Monopolistic Firm?

In the present paper, we examine the effect of increasing uncertainty of immigrants’ growth on the optimal timing of investment of a firm that has a monopolistic power over the labor market. It is revealed that when the uncertainty of immigrants’ growth is more than a threshold level, increasing uncertainty of immigrants’ growth accelerates the optimal timing of firms’ investment and enhances the economic growth, even if the uncertainty of immigrants’ growth is formulated by the geometric Brownian motion, which is in sharp contrast to the standard result that an increase in the uncertainty postpones the optimal timing. With an increase in the immigrants over the past ten years, workforces in the host countries have been growing significantly to the extent that the immigrants represent 70% of the increase in the workforce in Europe, and 47% in the United States as OECD indicates. In the present paper, we attempted to investigate the effect of increased uncertainty caused by the growi...

Education Policy Implementation: A Mechanism for Enhancing Primary Education Development in Zanzibar

Education is one of the fundamental rights of individuals; therefore, the government of a country needs to develop and strengthen educational policy and quality as well as to ensure that everyone has equal access to basic education. The improvement of access and quality of education in the world is becoming as an essential factor in development, whereas the basic education (primary school), is acknowledged as a foundation of the higher educational development for every country. To fulfill this goal, governments introduce several policies and procedures; however, it requires some reforms and participation from the politician, policymakers, and other stakeholders to re-examine educational policy so that it can lead to multiplication and betterment of the reforms. Educational reforms actually focus on accountability. A positive educational development and reform is very challenging and needs more effort and strategy on how to use and utilize the resources effectively as such it can achie...