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HAPRAP: a haplotype-based iterative method for statistical fine mapping using GWAS summary statistics

Fine mapping is a widely used approach for identifying the causal variant(s) at disease-associated loci. Standard methods (e.g. multiple regression) require individual level genotypes. Recent fine mapping methods using summary-level data require the pairwise correlation coefficients ([Formula: see t...

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Published in:Bioinformatics (Oxford, England) England), 2017-01, Vol.33 (1), p.79-86
Main Authors: Zheng, Jie, Rodriguez, Santiago, Laurin, Charles, Baird, Denis, Trela-Larsen, Lea, Erzurumluoglu, Mesut A, Zheng, Yi, White, Jon, Giambartolomei, Claudia, Zabaneh, Delilah, Morris, Richard, Kumari, Meena, Casas, Juan P, Hingorani, Aroon D, Evans, David M, Gaunt, Tom R, Day, Ian N M
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cited_by cdi_FETCH-LOGICAL-c444t-30afbaaeb948cd2546bdf4ef346a5275be3d5d869f7e7a750f0cae7b065a97313
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container_title Bioinformatics (Oxford, England)
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creator Zheng, Jie
Rodriguez, Santiago
Laurin, Charles
Baird, Denis
Trela-Larsen, Lea
Erzurumluoglu, Mesut A
Zheng, Yi
White, Jon
Giambartolomei, Claudia
Zabaneh, Delilah
Morris, Richard
Kumari, Meena
Casas, Juan P
Hingorani, Aroon D
Evans, David M
Gaunt, Tom R
Day, Ian N M
description Fine mapping is a widely used approach for identifying the causal variant(s) at disease-associated loci. Standard methods (e.g. multiple regression) require individual level genotypes. Recent fine mapping methods using summary-level data require the pairwise correlation coefficients ([Formula: see text]) of the variants. However, haplotypes rather than pairwise [Formula: see text], are the true biological representation of linkage disequilibrium (LD) among multiple loci. In this article, we present an empirical iterative method, HAPlotype Regional Association analysis Program (HAPRAP), that enables fine mapping using summary statistics and haplotype information from an individual-level reference panel. Simulations with individual-level genotypes show that the results of HAPRAP and multiple regression are highly consistent. In simulation with summary-level data, we demonstrate that HAPRAP is less sensitive to poor LD estimates. In a parametric simulation using Genetic Investigation of ANthropometric Traits height data, HAPRAP performs well with a small training sample size (N 
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1460-2059
1367-4811
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source Oxford University Press Open Access; PubMed Central
subjects bioinformatics
Chromosome Mapping - methods
gall bladder
Gene Frequency
Genome-Wide Association Study
Genotype
Haplotypes
Humans
Linkage Disequilibrium
loci
meta-analysis
Original Papers
Polymorphism, Single Nucleotide
prediction
Quantitative Trait, Heritable
quantitative traits
regression analysis
Sample Size
single nucleotide polymorphism
Software
title HAPRAP: a haplotype-based iterative method for statistical fine mapping using GWAS summary statistics
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