[ExI] bikers again

[Keith Henson]

On Fri, Sep 4, 2020 at 10:29 PM Dylan Distasio via extropy-chat
<extropy-chat at lists.extropy.org> wrote:
>
> On Sat, Sep 5, 2020, 12:33 AM spike jones via extropy-chat <extropy-chat at lists.extropy.org> wrote:
>>
>> Keith was the one who hipsterized me to how viruses don’t have DNA, they have RNA.  But I had heard that polymerase chain reaction is not a reliable amplifier of RNA, only DNA.
>
> Two comments, many viruses do have DNA.   CV-19 is not one of them though.

Correct.

I have no idea how Spike could have gotten such inaccurate information
from me,  I have understood that there are DNA and RNA viruses for
decades.  Smallpox, herpes, and the chickenpox are caused by DNA
viruses.   Influenza, rabies, and COVID-19 are RNA viruses.  The
misunderstanding could have been cured by a short visit to Wikipedia

"Most eukaryotic viruses, including most human, animal, and plant
viruses, are RNA viruses, although eukaryotic DNA viruses are also
common.[44][49]"

https://en.wikipedia.org/wiki/Baltimore_classification#Host_range

Some time ago (at least a year) I was impressed by an article (in
Science I think) which discussed positive selection of genes from
Neanderthals.  The article noted that around 6000 genes (of the 20,000
active in humans) were associated with virus resistance, about half
against DNA and half against RNA viruses.  Wow.  Close to 1/3 of the
human genome is associated with virus resistance.

You understand this subject.

Keith

> There are no issues with RT-PCR used for RNA detection in terms of protocol.  There's just an extra step in the beginning using reverse transcriptase to get a DNA strand to amplify from the RNA, and then it's just like regular PCR.
>>
>> a?  If so, it would explain why the people who use the covid tests every day say they are notoriously unreliable: they are using PCR to amplify RNA.  My nurse cousin thinks they have an unacceptably high false positive rate.
>>
>> spike
>
>
> It's actually very accurate, the potential issue is with sensitivity being too high.  Even a very small amount of RNA can be detected that may not be biologically active.
>
> Sensitivity issue:
> https://www.advisory.com/daily-briefing/2020/09/01/covid-tests
>
> Protocol:
> https://www.iaea.org/newscenter/news/how-is-the-covid-19-virus-detected-using-real-time-rt-pcr
>