FactCheck Social Media

PCR inventor – who died in 2019 – did not say his test won’t work for COVID-19 infections

2020-07-22 17:35:35

The Statement

A video on Facebook includes a claim that the inventor of the PCR test – one of the main tests used to detect COVID-19 –  said the tests do not work to properly diagnose COVID-19 infections.

The video, posted to a Facebook page called “NO CONSENT : For We Are Young and Free”, features a man criticising a July 18 article in The Australian newspaper about COVID-19 conspiracy theorists.

The speaker reads a number of quotes and attributes them to the inventor of the PCR test, the late US biochemist Kary B Mullis. Among the attributed quotes is the following: “PCR basically takes a sample of your cells and amplifies any DNA to look for viral sequences, i.e. bits of non-human DNA that seem to match parts of a known viral genome. The problem is the test is known not to work”.

Another attributed quote is: “the idea these kits can isolate a specific virus like COVID-19 is nonsense”.

The video has been viewed more than 3,100 times and attracted more than 120 comments since it was posted on July 18, 2020.

Similar claims about PCR testing have appeared online including here, here and here.

Facebook post screenshot
 A Facebook video claims the PCR test inventor said the tests do not effectively diagnose COVID-19. 

The Analysis

The quotes attributed to PCR test inventor Dr Kary B. Mullis are not from the Nobel Prize-winning American biochemist. The quotes have appeared online with various attributions online since March, 2020. Dr Mullis died in August, 2019, before the emergence of the SARS-CoV-2 virus and the COVID-19 pandemic.

The earliest example of the quoted lines found by AAP FactCheck is an entry published between March 13 and March 18, according to internet archive Wayback Machine, on a website that claims terrorist attacks such as 9/11 were staged. The lines on the website, copied below, are identical to the purported quotes read out in the video except for one omitted paragraph, shown in bold. They are not attributed to Dr Mullis but to an online commenter called “VirusGuy”:

PCR basically takes a sample of your cells and amplifies any DNA to look for ‘viral sequences’, i.e. bits of non-human DNA that seem to match parts of a known viral genome.

The problem is the test is known not to work.

It uses ‘amplification’ which means taking a very very tiny amount of DNA and growing it exponentially until it can be analysed. Obviously any minute contaminations in the sample will also be amplified leading to potentially gross errors of discovery.

Additionally, it’s only looking for partial viral sequences, not whole genomes, so identifying a single pathogen is next to impossible even if you ignore the other issues.

(Omitted: The Mickey Mouse test kits being sent out to hospitals, at best, tell analysts you have some viral DNA in your cells. Which most of us do, most of the time. It may tell you the viral sequence is related to a specific type of virus – say the huge family of coronavirus. But that’s all.)

The idea these kits can isolate a specific virus like COVID-19 is nonsense.”

The page contents also appear, copied and pasted, in this Facebook post dated March 17, 2020.

In addition to the original comments coming from an anonymous online commenter, Dr Mullis died, aged 74, in August 2019, four months before the first signs of the novel coronavirus outbreak in China and six months before the World Health Organisation named the disease COVID-19, making it impossible for the late doctor to have spoken about COVID-19.

The same “quotes” have appeared elsewhere online, including on this site, presented as being from “a widely respected professional scientist in the US” on a medical forum.

Dr Mullis was awarded the Nobel Prize in Chemistry in 1993 for his invention of  Polymerase Chain Reaction (PCR), a laboratory method used to make a large number of copies of short sections of DNA from a very small sample of genetic material, enabling specific genes of interest to be detected or measured.

PCR testing is one of the two main tests used to detect a COVID-19 infection in Australia and has been approved by the government’s Therapeutic Goods Administration.

Dr Ian Mackay, a virologist and adjunct associate professor with the University of Queensland, told AAP FactCheck the claims read out about PCR testing in the video show “an extreme lack of understanding of PCR, PCR test design and use”.

One of the claims is that the process of DNA amplification, which grows a tiny amount of DNA exponentially, can also amplify contaminants leading to “potentially gross errors of discovery”.

Dr Mackay said laboratories have processes in place to account for and prevent PCR contamination, including having controls to alert them if contamination has occurred.

In response to the claim “the tests do not work”, Prof Mackay said the tests are “extremely effective at very sensitively and specifically detecting SARS-CoV-2”.

“The leading tests have also been tested on SARS-CoV-2 RNA from infected patients, isolated and grown in cells in the lab – so we know it is this virus that we’re detecting,” he said.

“The tests detect the viral sequences we expect them to and not other viruses.”

Regarding the claim in the video that it is “next to impossible” for PCR testing to identify a single pathogen because it only looks for partial viral sequences and not the whole COVID-19 sequence, Professor Mackay said PCR tests are in fact designed to look at partial viral sequences.

“That is by design, not an error or an oversight. We have only been able to quickly and relatively easily (compared to even a decade ago) detect entire viral genomes – the science of genomics – in very recent times. It is still costly, less sensitive and slower to determine the entire sequence of a virus compared to detecting its presence using a PCR test. And for cluster, outbreak, epidemic and pandemic control and for patient management – detection the virus (which real-time PCRs do) is all that is needed,” he said.

COVID-19 test
 A claim that the inventor of PCR tests said the tests don’t work in detecting COVID-19 is false. 

The Verdict

Based on the evidence, AAP FactCheck found the Facebook post to be false. The quotes in the video are not from PCR test inventor Kary B. Mullis, who died in August 2019, before the discovery of COVID-19. The claims instead appear to have originated from an anonymous online commenter.

Claims about the effectiveness of PCR tests are incorrect. Virology expert Professor Ian Mackay said the claims show “an extreme lack of understanding of PCR, PCR test design and use” and that PCR tests are “extremely effective at very sensitively and specifically detecting SARS-CoV-2”.

False – The primary claims of the content are factually inaccurate.

* AAP FactCheck is accredited by the Poynter Institute’s International Fact-Checking Network, which promotes best practice through a stringent and transparent Code of Principles. https://www.aap.com.au/