Ribonucleic acid in plasma from normal adults and multiple myeloma patients

Abstract

Reports of the presence of RNA in human plasma have been numerous, often suggesting that RNA in plasma is correlated with human disease. The authors critically examined the methods for determination of RNA in plasma. Lack of method specificity has caused previous workers to overestimate plasma RNA concentrations by more than 50-fold. To isolate RNA from plasma, the authors used both a phenol-chloroform extraction and a modified Schmidt-Thannhauser procedure. The authors show that RNA in plasma can be identified and quantified by alkaline hydrolysis of the plasma extract and subsequent separation of the resulting 2'- and 3'-mononucleotides by 'high-performance' liquid chromatography. The authors could not detect RNA in plasma from either apparently healthy, normal adults or multiple myeloma patients, but found 1.1 mg/l in the plasma of a patient with Waldenstrom's macroglobulinemia. The method is useful for the specific determination of RNA in plasma and will detect as little as 600 μg/l.