Test site customers report that system can detect a greater number of genes with higher sensitivity and specificity than other microarray technologies
Applied Biosystems has announced the worldwide commercial availability of the Applied Biosystems Expression Array system. The product combines highly sensitive gene detection capabilities with easy integration to Applied Biosystems's complementary gene expression products, such as its TaqMan gene expression assays, TaqMan low density array, Celera Discovery System (CDS), and real-time PCR systems.
Together, these systems provide a comprehensive and streamlined solution for studies of human gene expression.
Twelve institutions recently completed the final testing of the system, including the University of Iowa, Iowa City, Iowa, United States and Human Genetic Signatures.
"We are using the Expression Array System to study gene expression in brain tumors and the effect of pharmaceutical therapy on reversing abnormal expression.
"The quality of the data generated using the system has been outstanding and highly superior in terms of sensitivity and accuracy when compared with the cDNA microarrays we were previously using," said Greg Foltz, assistant professor, departments of Neurological Surgery and Neurology, University of Iowa.
"We decided to convert to this system for our gene expression work based on Applied Biosystems' history of technical leadership and high quality support, and our experience thus far has been excellent.
"In addition to the superior quality that we are seeing, we have found the system to be completely reliable and very easy to use".
"Human Genetic Signatures selected the Expression Array System over other previously used commercial microarray products, owing to its superb data reproducibility and user-friendly, annotated bioinformatics capabilities," said George Miklos, vice president and chief scientific officer of Human Genetic Signatures.
"We have experienced, first hand, the levels of variation produced by other microarray platforms and the difficulties of de-convoluting the associated bioinformatics problems that are particularly acute in our field of methylomics.
"This new microarray system addresses these serious challenges and allows us to integrate our advanced bisulphite and intercalating nucleic acid (INA) technologies with gene expression profiles and the personalised methylation signatures of human adult stem cells in aging, cancer, and in cellular therapeutics".
"Until now, the process of studying gene expression, from whole-genome analysis to gene quantification and single-gene analysis, has required multiple technologies that have not been coordinated or supported in an integrated workflow," said Michael Hunkapiller, president of Applied Biosystems.
"The Expression Array system not only includes improvements to address the limitations of existing commercial and homebrew technologies, but also makes the transition from global expression profiling on microarrays to the examination of a more focused set of candidate genes more efficient and productive for researchers involved in basic research, drug target validation, and pre-clinical drug development".
"Gene expression analysis is a large and fast-growing application within molecular biology research and pharmaceutical development," said Catherine Burzik, executive vice president of Applied Biosystems.
"We believe this system will be attractive to researchers who are interested in obtaining the highest sensitivity and specificity with access to hand curated and highly comprehensive annotation of the human genome.
"Additionally, our entry into the expression microarray market is an excellent complement to our gold-standard TaqMan-based products for quantitative gene expression. "Together, these products should enable our customers to develop more integrated workflows in line with our integrated science, or iScience, business strategy".
Well-defined and longer probe lengths coupled with chemiluminescent technology and highly porous nylon membranes result in the following advantages of the Applied Biosystems Expression Array system.
The Expression Array system detects up to 40% more genes when compared to conventional fluorescent microarrays.
The system achieves more than a ten-fold increase in sensitivity for the detection of low expressed genes.
High quality data can be obtained with the system from as low as 500ng of total RNA starting material with the potential to use smaller sample amounts depending on applications performed.
Every human transcript sequence was either hand curated or experimentally validated at Applied Biosystems.
Each probe is a part of a relational database that includes both Celera Genomics annotations and those in the public domain.
The database includes, for example, gene acronyms, gene names, cross-references for gene identification, public (GO) and Celera (Panther) gene ontologies, and other relevant information. Microarray results can be linked to the Celera Discovery System, where the precise location of each microarray probe is graphically aligned to the extensive annotative information found within CDS.
The gene identification information supplied with the Expression Array System database also allows access to the more than 22,000 validated, quantitative, TaqMan Gene Expression Assays to facilitate validation of microarray results, absolute quantification of transcripts, and investigation of alternative splicing.
Customers have completed final testing of the soon to be released mouse genome survey microarray.
The rat genome survey microarray is expected to be released later in calendar year 2004.
