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Updated: Jul 18, 2026
10:17
An Allele-specific Gene Expression Assay to Test the Functional Basis of Genetic Associations
Published on: November 3, 2010
Allelic association in the FRAX region
1Human Genetics Research Division, Southampton General Hospital, Hampshire, UK. se@soton.ac.uk
Annals of Human Genetics
|April 3, 2001
Summary
This study analyzed 7219 haplotypes in the FRAX region, finding that marker association declines exponentially with distance. A swept radius of 433 kb suggests high marker density is effective for genetic studies.
Area of Science:
- Genetics
- Population Genetics
Background:
- Sex chromosomes facilitate direct haplotype determination.
- Microsatellite markers are valuable tools in genetic association studies.
Purpose of the Study:
- To analyze haplotypes in the FRAX region using microsatellite markers.
- To estimate the extent of linkage disequilibrium and its decline with distance.
Main Methods:
- Analysis of 8 microsatellite markers from the FRAX region (Xq27-q28).
- Collection of 7219 independent haplotypes from a Wessex population.
- Estimation of epsilon (exponential decline of association) and swept radius.
Main Results:
- Allelic association strength correlates with allele frequency, being weaker for trinucleotide than dinucleotide repeats.
- The estimated swept radius of association was 433 kb.
- This distance is comparable to estimates for Single Nucleotide Polymorphisms (SNPs).
Conclusions:
- A marker density of 1/100 kb is predicted to be powerful for regions like FRAX.
- These findings suggest similar marker density strategies may be effective for SNP studies in multiple regions.
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