NO, DNA is a sequence of nucleotides, which codes for the instructions to produce proteins. PCR certainly will not amplify proteins.
It is true that primers (short strands of DNA that kick off the replication process) sometimes bind to DNA sequences that don't perfectly match their target. If the target and a slightly different sequence are both present, since the primers will bind much better to the former, the overwhelming majority of what you get will be the former, and you can sequence it without complication. If there is none of the former, you can get a tiny amount of replication of the latter, especially if you use a lower annealing temperature, and then with enough cycles, amplify that to the point where it is sequenceable. All this is the Good Ol' Fashioned method. Next Generation Sequencing, oof, don't ask this old mastodon.
PCR is used as a diagnostic tool regularly, and it is harder to ignore when it is coupled with sequencing. You can't say "Maybe it's just amplifying a piece of flu virus" when the sequence is right there on the screen. As for the claim that "high cycles have been mandated," please provide a link to support that. People running tests of any kind actually do not want everybody, all the time, to test positive for everything. That makes the test totally worthless. Most of us have had the experience of testing negative.
And finally, if this disease has been endemic in humans for tens of thousands of years, how come now it's suddenly killing hundreds of thousands of people?
![[personal profile]](https://www.dreamwidth.org/img/silk/identity/user.png)
branchandroot
Re: PCR test explanation
Date: 2021-09-10 12:43 pm (UTC)It is true that primers (short strands of DNA that kick off the replication process) sometimes bind to DNA sequences that don't perfectly match their target. If the target and a slightly different sequence are both present, since the primers will bind much better to the former, the overwhelming majority of what you get will be the former, and you can sequence it without complication. If there is none of the former, you can get a tiny amount of replication of the latter, especially if you use a lower annealing temperature, and then with enough cycles, amplify that to the point where it is sequenceable. All this is the Good Ol' Fashioned method. Next Generation Sequencing, oof, don't ask this old mastodon.
PCR is used as a diagnostic tool regularly, and it is harder to ignore when it is coupled with sequencing. You can't say "Maybe it's just amplifying a piece of flu virus" when the sequence is right there on the screen. As for the claim that "high cycles have been mandated," please provide a link to support that. People running tests of any kind actually do not want everybody, all the time, to test positive for everything. That makes the test totally worthless. Most of us have had the experience of testing negative.
And finally, if this disease has been endemic in humans for tens of thousands of years, how come now it's suddenly killing hundreds of thousands of people?