Statistical exploration of variation in quantitative two-dimensional gel electrophoresis
Artikel i vetenskaplig tidskrift, 2004
Two-dimensional gel electrophoresis is a major technique in global analysis at the protein
level. This paper presents an examination of spot volume data from three gel sets with radioactively
labeled yeast Saccharomyces cerevisiae proteins. A strong variance versus mean
dependence in data was found to be stabilized by applying a shifted logarithmic transformation.
However, transformed data showed a remaining substantial variance heterogeneity for
different proteins. Furthermore, examination of studentized residuals revealed that transformed
data were approximately normally distributed and that there were spatial correlations
among the measurement errors in the gel.
Two-dimensional gel electrophoresis