Automation of DNA and miRNA co‐extraction for miRNA‐based identification of human body fluids and tissues

Abstract

In the last years, microRNA (miRNA) analysis came into focus in the field of forensic genetics. Yet, no standardized and recommendable protocols for co-isolation of miRNA and DNA from forensic relevant samples have been developed so far. Hence, this study evaluated the performance of an automated Maxwell® 16 System-based strategy (Promega) for co-extraction of DNA and miRNA from forensically relevant (blood and saliva) samples compared to (semi-)manual extraction methods. Three procedures were compared on the basis of recovered quantity of DNA and miRNA (as determined by real-time PCR and Bioanalyzer), miRNA profiling (shown by Cq values and extraction efficiency), STR profiles, duration, contamination risk and handling. All in all, the results highlight that the automated co-extraction procedure yielded the highest miRNA and DNA amounts from saliva and blood samples compared to both (semi-)manual protocols. Also, for aged and genuine samples of forensically relevant traces the miRNA and DNA yields were sufficient for subsequent downstream analysis. Furthermore, the strategy allows miRNA extraction only in cases where it is relevant to obtain additional information about the sample type. Besides, this system enables flexible sample throughput and labor-saving sample processing with reduced risk of cross-contamination.

MicroRNA Based Liquid Biopsy: The Experience of the Plasma miRNA Signature Classifier (MSC) for Lung Cancer Screening

“…The minor risk of contamination, the higher reproducibility, and the economic time use are the main advantages of automated systems compared to manual isolation protocols. Moreover, automated extraction methods yielded the highest miRNA amounts from blood samples and the highest efficiency compared to manual protocols 36 .…”

Detection of microRNAs in DNA Extractions for Forensic Biological Source Identification

“…Some studies include DNase treatment as a step in a proposed RNA analysis protocol, while others have included it as a type of negative control or do not specify any DNase treatment being performed (). We observed that DNase‐treated extracts were less than or equal to one cycle different from untreated extracts for all isolation methods.…”

Pathophysiology and Clinical Utility of Non-coding RNAs in Epilepsy

“…A series of studies have reported that changes of miRNAs observed in certain biological fluids correlate with various pathological conditions suggesting that circulating miRNAs might be useful and informative biomarkers to reflect the pathological status of the body (Valentino et al, 2017 ; Wang, 2017 ; Zendjabil et al, 2017 ; Zhao et al, 2017 ). Evidence has emerged that miRNAs in blood or cerebrospinal fluid may serve as potential biomarkers of brain injury (Weber et al, 2010 ; Kulstein et al, 2016 ; Martinez and Peplow, 2016 ; Sirker et al, 2016 ; Wang, 2017 ). These miRNAs in biological fluids may come through the damaged blood–brain barrier after epilepsy onset or originate from controlled release in exosomes (Choi et al, 2017 ; Gourlay et al, 2017 ).…”