Journal of Probability and Statistics
Volume 2012 (2012), Article ID 419832, 12 pages
http://dx.doi.org/10.1155/2012/419832
Research Article

A Multinomial Ordinal Probit Model with Singular Value Decomposition Method for a Multinomial Trait

Soonil Kwon,1 Mark O. Goodarzi,1 Kent D. Taylor,1 Jinrui Cui,1 Y.-D. Ida Chen,1 Jerome I. Rotter,1 Willa Hsueh,2 and Xiuqing Guo1

1Medical Genetics Institute, Cedars-Sinai Medical Center, 8700 Beverly Boulevard, Paciffc Theatres Building, 4th Floor, Los Angeles, CA 90048, USA
2The Methodist Hospital Research Institute, The Methodist Hospital, 6670 Bertner Street R8-103, Houston, TX 77030, USA

Received 12 March 2012; Accepted 31 March 2012

Academic Editor: Yongzhao Shao

Copyright © 2012 Soonil Kwon et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

We developed a multinomial ordinal probit model with singular value decomposition for testing a large number of single nucleotide polymorphisms (SNPs) simultaneously for association with multidisease status when sample size is much smaller than the number of SNPs. The validity and performance of the method was evaluated via simulation. We applied the method to our real study sample recruited through the Mexican-American Coronary Artery Disease study. We found 3 genes (SORCS1, AMPD1, and PPARα) to be associated with the development of both IGT and IFG, while 5 genes (AMPD2, PRKAA2, C5, TCF7L2, and ITR) with the IGT mechanism only and 6 genes (CAPN10, IL4, NOS3, CD14, GCG, and SORT1) with the IFG mechanism only. These data suggest that IGT and IFG may indicate different physiological mechanism to prediabetes, via different genetic determinants.