You remember a while ago, I wrote about how GMO papaya creates a population of ‘papaya’ that has herd immunity against papaya ringspot virus, thus is able to protect non-GMO papaya from the virus?
Theyre trying to do a similar thing with chickens (any commercial bird, really– ducks, geese, turkeys, etc) and avian flu!
Fundamentally this is the same idea as the GMO papaya, but the way they are accomplishing it is different. With the papaya, the GMO plants themselves were resistant to the virus, thus stopped the spread to non-GMO papaya.
With the chickens, the GMO chickens are still susceptible to infection and death from a highly pathogenic bird flu variant… but they dont pass on the virus to surrounding chickens, GMO or no. So again, the GMO variant protects everything, even the ‘organic’ variants!
Yes, this is neat, but what makes it even more neatier is that the researchers arent really sure how this is working (cue: OH MA GAH GMO CHICKEN GIVIN MEH CANKER!). They set up their experiments thinking that they knew how it would work: They inserted an RNA expression cassette (fake gene where what you want is RNA, not a protein) that encodes a short-hairpin RNA that looks like this bit on the influenza RNA segments. You know how HIV-1 is a ‘sheet cake’ virus? One big genome that makes one big RNA that gets chopped up into smaller RNAs and proteins? Influenza is a cup-cake virus. It has 8 segments of its genome, each coding for a protein (well, 11 genes/8 segments, some cupcakes get cut in half, lol).
Each of those segments has to have a region on it that tells influenza polymerase to make its gene(s).
The introduced RNA hair-pin is that region. The viral genomes form the same RNA structure as the ‘fake’ RNA. So when its present in a cell that is infected with influenza, the ‘fake’ RNA binds up all the polymerase, so its not binding to the viral genome–>replicating, thus tripping up the viruses life-cycle.
Even better? You know how influenza mutates/drifts all the time, so thats why we have to make different vaccines every year? This ‘fake’ RNA is totally conserved in influenza. ‘Fake’ RNA will work on any influenza– no matter what year it is or how the proteins targeted by antibodies change.
Well, they screened for modified chickens where what they did worked… but when they went to investigate why it worked, it didnt work the way they thought it would (IT MUST CAUSE CAAAAANKER! GMO=CANKER!!!!).
The question is hanging there– Why does this approach work in these chickens? What is really going on?
This means regardless of whether these chickens ever become a normal part of our commercial chicken populations– we now have a new tool for maybe figuring out a new target/new therapies for influenza! Maybe something is going on here that could help humans, short of GMO humans– something that can be turned into a drug that works on any influenza variant. Its always nice to have a few extra tricks up your sleeve with viruses, but especially highly contagious, fast moving, potentially very deadly influenza.