The ability of PCR to amplify a single molecule for analysis was
soon recognised and exploited. In 1990 Jeffreys et al. [3] published
on the use of single molecule PCR to study minisatellite evolution
and Ruano et al. [4] published on the use of single molecule PCR
to analyse haplotyping. Single molecule PCR continues to be a useful
approach to study a target of interest. I searched Medline and
Google Scholar using the search terms of “single molecule” and
“PCR”, and found 4–10 publications annually in subsequent years.
“Single molecule PCR” is probably a more descriptive term than
“digital PCR” when referring to the process of PCR cloning of a target
molecule in order to perform qualitative analysis, as it refers to
the target molecule rather than to the signal.