Related Experiment Video
Updated: Jun 8, 2026
13:33
Infinium Assay for Large-scale SNP Genotyping Applications
Published on: November 19, 2013
Interrogating local population structure for fine mapping in genome-wide association studies.
Huaizhen Qin1, Nathan Morris, Sun J Kang
1Department of Epidemiology and Biostatistics, Case Western Reserve University, Cleveland, OH, USA.
Bioinformatics (Oxford, England)
|October 5, 2010
Summary
Adjusting for local ancestry improves genetic association studies by preventing false positives from population structure. This method enhances fine mapping for complex disease susceptibility genes.
Area of Science:
- Genetics
- Population Genetics
- Statistical Genetics
Background:
- Genetic association studies require adjustment for population structure to prevent bias.
- Population structure can vary across genomic regions due to factors like migration and selection.
- Current methods often adjust for global ancestry, which may not fully account for regional variations.
Purpose of the Study:
- To introduce and evaluate a method for interrogating local population structure for improved genetic association analysis.
- To enhance the accuracy of fine mapping for disease susceptibility genes by accounting for local ancestry.
- To compare the effectiveness of local versus global ancestry adjustment in controlling for population stratification.
Main Methods:
- Development and simulation of methods to adjust for local population structure.
- Genome-wide dataset simulations to assess false positive rates.
- Application of local and global ancestry adjustment methods to real genome-wide association study datasets (European Americans, African Americans, Nigerians).
Main Results:
- Adjusting for global ancestry can lead to false positives when local population structure is a significant confounder.
- Adjusting for local ancestry effectively prevents false positives arising from local population structure.
- Local ancestry adjustment improved fine mapping accuracy and successfully removed a spurious association between LCT gene SNPs and height in European Americans.
- European Americans and African Americans exhibited greater local ancestry variability than Nigerians.
Conclusions:
- Interrogating local population structure offers a more accurate approach to genetic association studies than relying solely on global ancestry.
- Local ancestry adjustment is crucial for reliable fine mapping of disease genes, especially in populations with heterogeneous ancestry.
- The proposed method enhances the robustness of genome-wide association studies by mitigating confounding effects of local population structure.
Related Concept Videos
01:11Genome-wide Association Studies-GWAS
Genome-wide association studies or GWAS are used to identify whether common SNPs are associated with certain diseases. Suppose specific SNPs are more frequently observed in individuals with a particular disease than those without the disease. In that case, those SNPs are said to be associated with the disease. Chi-square analysis is performed to check the probability of the allele likely to be associated with the disease.
GWAS does not require the identification of the target gene involved in...
GWAS does not require the identification of the target gene involved in...
01:25What is Population Genetics?
A population is composed of members of the same species that simultaneously live and interact in the same area. When individuals in a population breed, they pass down their genes to their offspring. Many of these genes are polymorphic, meaning that they occur in multiple variants. Such variations of a gene are referred to as alleles. The collective set of all the alleles within a population is known as the gene pool.While some alleles of a given gene might be observed commonly, other variants...