Overview: The Affymetrix porcine genome microarray (http:// www.affymetrix.com/products/arrays/specific/porcine.affx) is minimally annotated. Less than 10% of the probe sets on this array are described with gene names, posing a challenge to biological interpretation of data. Lack of annotation is likely due to the limited availability of full-length porcine cDNA sequence. Presented here is a st...

We report and model a previously undescribed systematic error causing spurious excess correlations that depend on the distance between probes on Affymetrix® microarrays. The phenomenon affects pairs of features with large chip separations, up to over 100 probes apart. The effect may have a significant impact on analysis of correlations in large collections of expression data, where the systemat...

We analyze publicly available data on Affymetrix microarrays spike-in experiments on the human HGU133 chipset in which sequences are added in solution at known concentrations. The spike-in set contains sequences of bacterial, human and artificial origin. Our analysis is based on a recently introduced molecular-based model [E. Carlon and T. Heim, Physica A 362, 433 (2006)] which takes into accou...

Introduction Genome-wide association studies seek to identify variation in the human genome which underlies a particular disease, drug response, diagnosis, or prognostic outcome. The cataloging of human variation and subsequent association analysis has traditionally focused on single nucleotide polymorphisms (SNPs). This assessment of common SNP variation in human disease has proven fruitful; m...

The intent of this chapter is to provide the reader with a review of GeneChip technology and the complete system it represents, including its versatility, components, and the exciting applications that are enabled by this platform. The following aspects of the technology are reviewed: array design and manufacturing, target preparation, instrumentation, data analysis, and both current and future...

High density oligonucleotide array technology is widely used in many areas of biomedical research for quantitative and highly parallel measurements of gene expression. Affymetrix GeneChip arrays are the most popular. In this technology each gene is typically represented by a set of 11-20 pairs of probes. In order to obtain expression measures it is necessary to summarize the probe level data. U...

MOTIVATION Microarray designs have become increasingly probe-rich, enabling targeting of specific features, such as individual exons or single nucleotide polymorphisms. These arrays have the potential to achieve quantitative high-throughput estimates of transcript abundances, but currently these estimates are affected by biases due to cross-hybridization, in which probes hybridize to off-target...