Statistical exploration of variation in quantitative two-dimensional gel electrophoresis data.
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.
Gustafsson
John S
JS
Department of Mathematical Statistics, Chalmers University of Technology, Göteborg, Sweden. johng@math.chalmers.se
Ceasar
Robert
R
Glasbey
Chris A
CA
Blomberg
Anders
A
Rudemo
Mats
M
D000704:Analysis of Variance; D015180:Electrophoresis, Gel, Two-Dimensional / Q000379:methods*; D016678:Genome; D015233:Models, Statistical; D040901:Proteomics / Q000379:methods*; D015203:Reproducibility of Results; D012441:Saccharomyces cerevisiae / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000032:analysis* / Q000737:chemistry; D012965:Sodium Chloride / Q000737:chemistry
D029701:Saccharomyces cerevisiae Proteins; D012965:Sodium Chloride