Assessing batch effects of genotype calling algorithm BRLMM for the Affymetrix GeneChip Human Mapping 500 K array set using 270

Background: Genome-wide association studies (GWAS) aim to identify genetic variants (usually single nucleotide polymorphisms [SNPs]) across the entire human genome that are associated with phenotypic traits such as disease status and drug response. Highly accurate and reproducible genotype calling are paramount since errors introduced by calling algorithms can lead to inflation of false associations between genotype and phenotype. Most genotype calling algorithms currently used for GWAS are based on multiple arrays. Because hundreds of gigabytes (GB) of raw data are generated from a GWAS, the samples are typically partitioned into batches containing subsets of the entire dataset for genotype calling. High call rates and accuracies have been achieved. However, the effects of batch size (i.e., number of chips analyzed together) and of batch composition (i.e., the choice of chips in a batch) on call rate and accuracy as well as the propagation of the effects into significantly associated...

• Type: Journal
• Year: 2008
• Where: BMCBI
• Authors: Huixiao Hong, Zhenqiang Su, Weigong Ge, Leming M. Shi, Roger Perkins, Hong Fang, Joshua Xu, James J. Chen, Tao Han, Jim Kaput, James C. Fuscoe, Weida Tong
• Keywords: Batch Compositions, Batch Size, BMCBI 2007, BMCBI 2008, Genotype