gb-2005-6-4-p4 GBJ Deposited research article <p>A novel scheme to assess factors involved in the reproducibility of DNA-microarray data</p> van Hijum AFT Sacha de Jong Anne Baerends JS Richard Karsens A Harma Kramer E Naomi Larsen Rasmus den Hengst D Chris Albers J Casper Kok Jan Kuipers P Oscar o.p.kuipers@rug.nl

Department of Molecular Genetics, University of Groningen, Groningen Biomolecular Sciences and Biotechnology Institute, PO Box 14, 9750 AA Haren, the Netherlands

Groningen Bioinformatics Centre, University of Groningen, Groningen Biomolecular Sciences and Biotechnology Institute, PO Box 14, 9750 AA Haren, the Netherlands

 Genome Biology 1465-6906 2005 6 4 P4 http://genomebiology.com/2005/6/4/P4 This was the first version of this article to be made available publicly. 10.1186/gb-2005-6-4-p4 3 3 2005 3 3 2005 2005 BioMed Central Ltd

A novel scheme to assess factors involved in the reproducibility of DNA-microarray data

In order to provide a quick and robust method for assessing data quality and sources of errors in DNA-microarray experiments a novel and cost-effective validation scheme was devised, implemented, and employed. The method was validated using Lactococcus lactis IL1403 amplicon-based DNA-microarray experiments. It was shown that the validation scheme allows determining conditions that could be improved to yield even higher DNA-microarray data quality.

Abstract

Background

In research laboratories using DNA-microarrays, usually a number of researchers perform experiments, each generating possible sources of error. There is a need for a quick and robust method to assess data quality and sources of errors in DNA-microarray experiments. To this end, a novel and cost-effective validation scheme was devised, implemented, and employed.

Results

A number of validation experiments were performed on Lactococcus lactis IL1403 amplicon-based DNA-microarrays. Using the validation scheme and ANOVA, the factors contributing to the variance in normalized DNA-microarray data were estimated. Day-to-day as well as experimenter-dependent variances were shown to contribute strongly to the variance, while dye and culturing had a relatively modest contribution to the variance.

Conclusions

Even in cases where 90 % of the data were kept for analysis and the experiments were performed under challenging conditions (e.g. on different days), the CV was at an acceptable 25 %. Clustering experiments showed that trends can be reliably detected also from (very) lowly expressed genes. The validation scheme thus allows determining conditions that could be improved to yield even higher DNA-microarray data quality.

 Bioinformatics Methods Genome studies Microbiology and parasitology