RNA diagnostics: real-time RT-PCR strategies and promising novel target RNAs.

Ribonucleic acid (RNA) is a multifunctional type of molecule, playing critical roles in protein biosynthesis and regulation. In recent years, suppression of protein translation by so-called microRNAs came into the focus of research, especially because deregulation of this process has been shown to play a role in malignant transformation. Furthermore, RNA molecules circulating in the blood have been revealed as a novel class of markers for diagnosis of cancers. Moreover, genetic information of some pathogens is stored as RNA, allowing their sensitive detection using nucleic acid amplification techniques. In this article, the principle of detecting different RNA types by real-time reverse-transcription polymerase chain reaction applications is described. Furthermore, the emerging use of microRNA and circulating RNA profiles complementing the broad spectrum of RNA diagnosis is discussed.