It has become widely recognized that most complex diseases result from many genes, with each gene only having a modest effect on the disease. Linkage analysis, a very effective method at mapping rare disease for which single gene is sufficient to cause disease, is less successful in localizing complex disease genes. It is believed that direct association approach is more powerful for identify common variants conferring modest risk. For a whole-genome scan, however, direct association is currently impractical, because it requires the genotypes at hundreds of thousands or millions of markers. Admixture mapping, an association-based approach using the information generated by recent population admixture, offers a promising but as yet untested methods for performing a whole-genome scan. The key advantage of admixture mapping is that while it is based on directly associating sections of the genome with disease, it only needs about 1% of markers for direct association studies. Although the idea of admixture mapping is simple, its practical application has awaited the development of statistical methods. This project will develop novel statistical methods for admixture mapping in whole-genome scan and further in candidate region studies using the sample from an admixture population, especially African-American population. First, a new method to estimate the ancestral status and allele frequencies in the founding populations will be developed. Based on the estimation method, statistical tests to test for linkage in genome scan and the tests to test for linkage and for association separately in candidate region studies will be proposed. In this project, it is also proposed to explore the pattern of LD caused by the recent admixture of two founding populations, and to evaluate the precision and the power of the methods by using extensive simulation studies.

Agency
National Institute of Health (NIH)
Institute
National Human Genome Research Institute (NHGRI)
Type
Small Research Grants (R03)
Project #
5R03HG003613-02
Application #
7126867
Study Section
Genomics, Computational Biology and Technology Study Section (GCAT)
Program Officer
Brooks, Lisa
Project Start
2005-09-26
Project End
2008-08-31
Budget Start
2006-09-01
Budget End
2007-08-31
Support Year
2
Fiscal Year
2006
Total Cost
$74,449
Indirect Cost
Name
Michigan Technological University
Department
Biostatistics & Other Math Sci
Type
Schools of Arts and Sciences
DUNS #
065453268
City
Houghton
State
MI
Country
United States
Zip Code
49931
Wang, Xuexia; Zhang, Shuanglin; Sha, Qiuying (2009) A new association test to test multiple-marker association. Genet Epidemiol 33:164-71
Qin, Huaizhen; Feng, Tao; Harding, Scott A et al. (2008) An efficient method to identify differentially expressed genes in microarray experiments. Bioinformatics 24:1583-9
Zhang, Zhaogong; Zhang, Shuanglin; Wong, Man-Yu et al. (2008) An ensemble learning approach jointly modeling main and interaction effects in genetic association studies. Genet Epidemiol 32:285-300
Feng, Tao; Zhang, Shuanglin; Sha, Qiuying (2007) Two-stage association tests for genome-wide association studies based on family data with arbitrary family structure. Eur J Hum Genet 15:1169-75
Zhang, Zhaogong; Zhang, Shuanglin; Sha, Qiuying (2007) A multi-marker test based on family data in genome-wide association study. BMC Genet 8:65
Sha, Qiuying; Chen, Huann-Sheng; Zhang, Shuanglin (2007) A new association test using haplotype similarity. Genet Epidemiol 31:577-93
Sha, Qiuying; Zhang, Xihuan; Zhu, Xiaofeng et al. (2006) Analytical correction for multiple testing in admixture mapping. Hum Hered 62:55-63
Zhu, Xiaofeng; Zhang, Shuanglin; Tang, Hua et al. (2006) A classical likelihood based approach for admixture mapping using EM algorithm. Hum Genet 120:431-45
Sha, Qiuying; Zhu, Xiaofeng; Zuo, Yijun et al. (2006) A combinatorial searching method for detecting a set of interacting loci associated with complex traits. Ann Hum Genet 70:677-92