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Updated: Jul 7, 2026
10:17
An Allele-specific Gene Expression Assay to Test the Functional Basis of Genetic Associations
Published on: November 3, 2010
Haplotypic analysis of Wellcome Trust Case Control Consortium data
Brian L Browning1, Sharon R Browning
1Department of Statistics, The University of Auckland, Private Bag 92019, Auckland, New Zealand, b.browning@auckland.ac.nz.
Human Genetics
|January 29, 2008
Summary
Localized haplotype clustering identified novel disease-associated loci for type 1 diabetes, type 2 diabetes, and hypertension. This multilocus method surpassed single-marker tests in detecting genetic variants for common diseases.
Area of Science:
- Genetics
- Statistical Genetics
- Genomic Association Studies
Background:
- Genome-wide association studies (GWAS) are crucial for identifying genetic variants underlying common diseases.
- Single-marker tests have limitations in detecting complex genetic associations.
- Novel statistical methods are needed to improve the power of GWAS.
Purpose of the Study:
- To apply a novel multilocus association testing method, localized haplotype clustering, to identify disease-associated loci.
- To compare the performance of localized haplotype clustering against single-marker tests.
- To assess the impact of stringent genotype quality filtering on reducing false-positive results.
Main Methods:
- Utilized Wellcome Trust Case Control Consortium data comprising 14,000 cases and 3,000 controls.
- Applied localized haplotype clustering and single-marker tests to Affymetrix 500 K array data.
- Performed rigorous data quality filtering and genotype quality thresholding.
- Used Beagle software for simultaneous phasing of 16,000 individuals.
Main Results:
- Identified three statistically robust disease-associated loci: 10p15.1 (Type 1 Diabetes), 12q15 (Type 2 Diabetes), and 15q26.2 (Hypertension).
- Detected association of 9p21.3 with Type 2 Diabetes, though it did not pass quality filters.
- Replication of 10p15.1 (T1D) and 9p21.3 (T2D) associations in independent datasets.
- Localized haplotype cluster analysis demonstrated superior performance over single-marker analysis.
Conclusions:
- Localized haplotype clustering is a powerful method for detecting disease-associated variants, outperforming traditional single-marker approaches.
- Stringent quality control is essential for minimizing false positives in genetic association studies.
- The identified loci warrant further investigation for their role in common diseases.
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...
01:05Single Nucleotide Polymorphisms-SNPs
A single nucleotide polymorphism or SNP is a single nucleotide variation at a specific genomic position in a large population. It is the most prevalent type of sequence variation found in the human genome. Point mutations that occur in more than 1% of the population qualify as SNPs. These are present once every 1000 nucleotides on an average in the human genome. Replacement of a purine with another purine (A/G) or a pyrimidine with another pyrimidine (C/T) is known as a transition. In contrast,...