A number of microarray studies use an experimental design in which experimental and reference RNA samples are transcribed into cDNA molecules, labeled with different fluorescent dyes (typically Cy5 and Cy3) and co-hybridized to the same microarray slide [ 3].
The RNAs used in these experiments were independent of those used for microarray studies.
Bayesian framework has been used for differential expression analysis of microarray study (Baldi and Long, 2001; Gottardo et al., 2003).
Using previously published outcomes of microarrays studies on aged murine oocytes (Hamatani et al., 2004; Pan et al., 2008), we established that expression of genes involved in mitochondrial metabolism was reduced by aging.
Second, the use of microarrays in studies in mammalian species other than human and rodents, for example nonhuman primates, bovine, sheep and porcine may advance our understanding of human health and disease, for example the use of animal models in drug target validation.
With the use of microarray analysis, extensive studies have been focused on identifying morphine-induced changes in gene expression [ 6– 19].
Systematic identification of candidate genes and new pathways related to intramuscular fat deposition in chicken breast tissues has also been made using gene expression profiles of two distinct breeds [ 27] showing the wide use of microarray in gene expression studies and identification of important pathways and biological processes in chicken.
Overall, the use of microarray technologies for the study of bladder cancer remains a new research field.
The increased use of microarray expression profiling to study both the molecular biology of cancer and the cellular physiology of difficult-to-isolate cell types has led to a growing need for methods that allow the use of limiting quantities of RNA.
We conclude that the optimum use of microarrays in clinical studies requires further optimisation and standardisation of methodology and reporting, together with improvements in clinical study design.
