Testing for Differentially-Expressed Genes by Maximum-Likelihood Analysis of Microarray Data

Although two-color uorescent DNA microarrays are now standard equipment in many molecular biology laboratories, methods for identifying differentially expressed genes in microarray data are still evolving. Here, we report a re ned test for differentially expressed genes which does not rely on gene expression ratios but directly compares a series of repeated measurements of the two dye intensities for each gene. This test uses a statistical model to describe multiplicative and additive errors in uencing an array experiment, where model parameters are estimated from observed intensities for all genes using the method of maximum likelihood. A generalized likelihood ratio test is performed for each gene to determine whether, under the model, these intensities are signi cantly different. We use this method to identify signi cant differences in gene expression among yeast cells growing in galactose-stimulating versus non-stimulating conditions and compare our results with current approaches...

• Type: Journal
• Year: 2000
• Where: JCB
• Authors: Trey Ideker, Vesteinn Thorsson, Andrew F. Siegel, Leroy E. Hood
• Keywords: DNA Microarray, Expressed Genes, Gene Expression, JCB 2000