title: Statistical models in assessing fold change of gene expression in real-time RT-PCR experiments.
abstract: Real-time RT-PCR has been frequently used in quantitative research in molecular biology and bioinformatics. It provides remarkably useful technology to assess expression of genes. Although mathematical models for gene amplification process have been studied, statistical models and methods for data analysis in real-time RT-PCR have received little attention. In this paper, we briefly introduce current mathematical models, and study statistical models for real-time RT-PCR data. We propose a generalized estimation equations (GEE) model that properly reflects the structure of repeated data in RT-PCR experiments for both cross-sectional and longitudinal data. The GEE model takes the correlation between observations within the same subjects into consideration, and prevents from producing false positives or false negatives. We further demonstrate with a set of actual real-time RT-PCR data that different statistical models yield different estimations of fold change and confidence interval. The SAS program for data analysis using the GEE model is provided to facilitate easy computation for non-statistical professionals.
authors.affiliation: Department of Epidemiology, Michigan State University, East Lansing, MI 48824, USA.
authors.forename: Wenjiang J
authors.initials: WJ
authors.lastname: Fu
authors.forename: Jianbo
authors.initials: J
authors.lastname: Hu
authors.forename: Thomas
authors.initials: T
authors.lastname: Spencer
authors.forename: Raymond
authors.initials: R
authors.lastname: Carroll
authors.forename: Guoyao
authors.initials: G
authors.lastname: Wu
mesh_terms: D000273:Adipose Tissue / Q000737:chemistry / Q000201:enzymology; D000818:Animals; D015870:Gene Expression / Q000235:genetics*; D008957:Models, Genetic; D015233:Models, Statistical; D051381:Rats; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods*; D012680:Sensitivity and Specificity