Enormous quantities of gene-sequence data are pouring out of labs thanks to dramatic gains in DNA sequencing technology, but that's only a start. The real question is how genetic information translates into biological activity. Gene expression---the complex process by which some genes are turned on, others off---is an essential part of the functioning of an organism. It also can indicate, or be a factor in, many diseases. The mechanisms of gene regulation are poorly understood---recent research, for example, suggests that a great deal of gene regulation information may be encoded in long stretches of DNA previously written off as "junk."
Gene expression measurements impact everything from basic bioresearch to drug development and clinical diagnostics. The most powerful tool for studying gene expression is the microarray, a device that uses many thousands of DNA probes to make massively parallel measurements of gene activity. But the technology is beset by large uncertainties and unexplained variability in measurement. One experiment using three different microarray systems to measure the same sample found that under the most stringent criteria the three agreed on only four out of 275 genes identified.
NIST's multidisciplinary Metrology for Gene Expression Program seeks to improve the quality, reliability and comparability of gene expression measurements with microarrays. Working with instrument developers and users, the program will evaluate sources of error and variability in measurement, and will develop reference data, reference materials and measurement methods to enable quality assurance for the chemistry, detection methods and information processing used in microarray analysis.
A key partnership that helped inspire the program is the External RNA Control Consortium, a group of almost 50 organizations from industry, academic labs, federal agencies and other key stakeholders.