Rolf Turk, Ellen Sterrenburg, Judith Boer, GertJan van Ommen, Johan den Dunnen
Dept. of Human and Clinical Genetics / Leiden Genome Technology Center (LGTC),
Leiden University Medical Center, Leiden
One of the most profound qualities of the cDNA microarray technique is the ability of studying expression profiles at a large scale. This high-throughput system is based on determining expression levels of two different samples during each hybridization and subsequently calculating the ratio between these two levels. Due to a high number of variables each hybridization is prone to variations, which might lead to altered ratios. These variables include cDNA synthesis, labeling, hybridization and scanning. Various control experiments are developed to circumvent the alteration of ratios due to these variables. By eliminating the influence of these variables every experiment can be normalized and compared to other hybridizations.