Send to

Choose Destination
See comment in PubMed Commons below
J Pharmacol Toxicol Methods. 2009 Jan-Feb;59(1):44-9. doi: 10.1016/j.vascn.2008.10.003. Epub 2008 Nov 5.

Recovery of microarray-quality RNA from frozen EDTA blood samples.

Author information

  • 1Clinical Pharmacology, Bayer Schering Pharma AG, Berlin, Germany.



The availability of blood collection systems with RNA stabilizing additives (e.g. PAXgene) has opened the field for gene expression profiling in large multi-center clinical trials. Here, we investigated whether the PAXgene system also offers a method for extraction of RNA from frozen EDTA blood samples, which do not yield RNA of high enough quality for RNA expression profiling, when extracted with standard protocols.


Whole blood was obtained from six healthy volunteers in conventional EDTA tubes and frozen. The thawed EDTA blood was transferred into PAXgene tubes, and the RNA was extracted using the PAXgene RNA extraction kit. Microarray analysis was performed to asses the effect of RNA quality on gene expression profiles.


The RNA yield of the transferred samples was 1.76+/-0.88 microg/ml. This yield was clearly lower than the yield from a PAXgene reference group (2.84+/-0.62 microg/ml), but considerably higher than the yield resulting from a standard protocol usually applied to fresh EDTA blood samples (0.07+/-0.06 microg/ml). The RNA integrity number (RIN) of the transferred samples was 6.1+/-0.8 as compared to 9.8+/-0.1 for the PAXgene reference. Microarray analysis of the extracted RNA suggested that samples with RIN values above 5 produce data that fulfill the quality criteria defined by the manufacturer.


The transfer of thawed EDTA blood into PAXgene blood collection tubes offers a method to recover sufficient RNA of acceptable quality for microarray experiments.

[PubMed - indexed for MEDLINE]
PubMed Commons home

PubMed Commons

How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Elsevier Science
    Loading ...
    Write to the Help Desk