dnature diagnostics & research


Here you will find the musings of John.  Some of these were written almost a decade ago now but they remain relevant today.  We welcome your feedback.

The solution (of your primers)

By John Mackay | 23/10/2019

Another old blog article – this one written originally in July 2010 : As PCR primers become less expensive, is there less care being paid to them? Throw in a diluent,a quick vortex and dilute for PCR? I hope this doesn’t sound too familiar because even in these days of real-time qPCR and various probe […]

This PCR is extremely Wittwer

By John Mackay | 14/08/2019

OK, confession time. I used to work some crazy hours in order to fit some library screening into a part time job while finishing my degree. No, that’s not the confession – more, when I put the PCR on I would sometimes look out the window and note the wind direction. Occasionally, very occasionally (*cough*) if the […]


By John Mackay | 20/06/2019

Designing primers for your high resolution melting is easy enough. A quick run with some known genotypes …. and look for the melting curve differences among samples. Too simple. But what about the temperature-neutral SNP’s? The what? A number of SNP’s ( ~ 4% in the human genome) have no affect on the melting temperature […]

Killing that DNA

By John Mackay | 08/11/2018

 You’ve done the hard work – you’ve got good quality RNA.  You’ve seen ribosomal bands on a gel (or *cough* Fragment Analyzer).  A good RQN/RIN (if that’s what you go by) and everything’s great. Now to get rid of the DNA Quick check (perform a PCR directly on appropriate amount of RNA) and often there’s […]

I have ‘what’ in my sample?

By John Mackay | 19/06/2017

Reagent contamination in PCR has long been documented – not only by operators but also from commercial sources long before those operators ever laid DNA-ridden hands on them. While contamination of some/many Taq polymerase enzymes with residual host E. coli DNA has had attention, little attention has been paid to the ubiquitous DNA extraction kits. […]