Single-cell Molecular Analysis: When an Experimental Technique Generates Conceptual Controversies

Abstract

The last decade has witnessed a rapid evolution of highly sensitive single-cell molecular analysis techniques. These techniques allow the simultaneous detection and quantification of mRNA and protein molecules in a large number of individual cells. Some of these methods are already commercialized, making them readily available to any interested lab. While the pitfalls concerning the experimental extraction of biocomponents (mRNA and protein) and analytical bioinformatic methods are widely discussed in the literature, little is known regarding the conceptual difficulties raised by single-cell methodologies. Considered and treated as pure technical difficulties, these issues are rarely discussed explicitly. This is a problem as conceptual difficulties precede technical ones and contribute, to a large extent, to the failure of techniques. Consequently, a new theoretical framework is urgently needed to make sense of the ever-increasing amount of data.