External RNA Control Consortium (ERCC)

The External RNA Control Consortium (ERCC) is an ad-hoc group with approximately 70 members from private, public, and academic organizations. The group was initiated in 2003 to develop a set of external RNA control transcripts that can be used to assess technical performance in gene expression assays. The external RNA controls will be added after RNA isolation, but prior to cDNA synthesis. They are being designed to evaluate whether the results for a given experiment are consistent with defined performance criteria. All ERCC work is intended to apply to quantitative, real-time reverse transcriptase polymerase chain reaction (QRT-PCR) assays as well as one-color and two-color microarray experiments.

The ERCC has worked together to define the desired properties of the transcripts, general protocols for their application, and an analysis scheme for performance assessment. In December 2003, the group developed a specification document that was discussed and refined in a public workshop at the National Institute of Standards and Technology (NIST). Protocols for the use of external RNA controls in clinical applications are included in the Molecular Methods 16-P document from the Clinical and Laboratory Standards Institute, and were developed in a formal, accredited, open, consensus forum including several ERCC members. The analysis approach was developed in a public workshop at NIST in June 2004, and is based upon the measurement of pooled transcripts at known concentrations.

In the past year, the ERCC has refined specifications, generated and collected control sequences, evaluated optimal polyadenylated (polyA) tail length and identified a path forward for access and distribution of the controls, as descibed in "Proposed Methods for Testing and Selecting the ERCC External RNA Controls". Input on the proposed methods is being solicited by e-mail at ercc@nist.gov.

 An ERCC Test Plan meeting is scheduled for October 4-5, 2005 at Lister Hill Auditorium at NIH, Bethesda, MD. For information about this meeting write ercc@nist.gov.

A general description of this activity is in the August 26, 2005, NIST Tech Beat.