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Discussion Starter #1
If you do a search on "genetic resistance to cwd", you will find many scientific papers that have found the presence of a gene in deer that gives them resistance to CWD. If this is true, it gives some hope for a natural way to control this disease. The deer with this gene should live longer, breed more and eventually elevate the number of healthy deer to the point where it is not a significant problem.

If this gene does exist, using sharpshooters and culling herds indiscriminately may do more harm that good. They would be killing the good with the bad and not allowing nature to take its course. It would be better to eliminate only the bad deer after they are tested. The deer identified as carrying the good gene could be marked of tagged so they are not shot. This will require a lot of test development and catch and release effort but helping nature do it naturally might be better in the long run than wiping out a herd temporarily.
 

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Does the research say anything about the deer that show no sign of the disease still being able to shed the prions? I have never heard of any species developing a resistance to a prion based disease. There is evidence that animals and birds can develop a resistance to EHD but that s a virus based disease.
 

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Discussion Starter #3
They are not developing a resistance. They are born with it due to their genetic makeup. I imagine if they are in contact with the prions, they not affected by them.
 

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Discussion Starter #6
So, in a couple hundred years, this will no longer be an issue.
If we find a way to save the ones with the good genes and cull the others maybe it won't take that long, No one is saying that killing all the deer in an infected area will solve the problem. If deer without the gene moves into that area they will just get sick from the prions and they will all have to be shot again.

Now if you shot 50 deer and replaced them with 50 deer with the right genes you would create a population the would not get sick from the prions. If a sick deer wandered in he might be less likely to breed or, if he did, maybe his offspring not get the disease because the mother has the gene. It may be that he would not get the disease unless both his parents carry a recessive gene and the offspring have a 25 percent chance of getting. Kind of like green eyes in humans. Rare but it happens,

I don't think it is an issue of the strongest survive but that the best genes do.
 

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Ahh, those with the best genes are the strongest. Of course that is contingent on that there actually is a resistance to the disease in certain animals. Which would be entirely new for prion diseases..
 

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Does the research say anything about the deer that show no sign of the disease still being able to shed the prions? I have never heard of any species developing a resistance to a prion based disease. There is evidence that animals and birds can develop a resistance to EHD but that s a virus based disease.

Here is an article about it. Study Shows Some Deer Genetically Resistant to Chronic Wasting Disease - Deer & Deer Hunting | Whitetail Deer Hunting Tips

I think it was Kramer from the comedy Seinfeld who said it best: Mother Nature is a mad scientist! Nowhere is this more apparent than when considering how different animals have physical characteristics that may look strange, but that are best suited to their environment. For example, whitetail deer are born with white spots, camouflaging and protecting them from predators.

Scientist Charles Darwin explained Mother Nature’s mad tendencies by natural selection. Harken back to high school biology class, where you probably learned about natural selection (a.k.a., survival of the fittest). Natural selection is the process by which certain species that possess genetic traits best adapted to their environment tend to survive and pass the genetic traits to offspring, while animals without these genetic traits tend to die off.

Chronic wasting disease is a perplexing issue for biologists, state wildlife agencies and hunters. The disease has been discovered in more than two dozen U.S. states and Canadian provinces. (Photo: Warden Micheal Hopper, Kansas Department of Wildlife, Parks & Tourism)
Chronic wasting disease is a perplexing issue for biologists, state wildlife agencies and hunters. The disease has been discovered in more than two dozen U.S. states and Canadian provinces. (Photo: Warden Micheal Hopper, Kansas Department of Wildlife, Parks & Tourism)

It’s important to remember what natural selection is, because it just may hold the key to dealing with chronic wasting disease (CWD). Unless you’ve been living in outer space you know that CWD has been killing deer, elk and moose for decades. Wild whitetails in Wisconsin have been hit particularly hard by the disease, with biologists first identifying it in the wild in 2002. The Wisconsin DNR tried unsuccessfully to eradicate CWD by hiring sharpshooters to eradicate all whitetails in the CWD core area. Hunters knew their efforts were in vain.

“The topography is heavily wooded and hilly, giving deer ample places to hide,” said Anthony Grabski, a biochemist, hunter and landowner in the original core Wisconsin CWD area. “Deer are also very evasive creatures, so it’s impossible to kill all of them.”

Thankfully, long gone are the days of Wisconsin trying to wipe out CWD by wiping out deer herds. Today the Badger State’s management of CWD is limited to monitoring its prevalence and spread. This passive management gives a nod to natural selection, and a recent study supports the approach.

University of Wisconsin-Madison researcher Stacie Robinson and her colleagues looked at tissue samples of harvested deer collected for six years in the core CWD area to identify a set of genes (genotype) that appear to make some whitetails genetically resistant to CWD. Statistical modeling showed that deer with a particular genotype were four times less likely to contract CWD, and if they did become infected, they lived 49 longer (8.2 months) than deer without the genotype.

Robinson and her colleagues estimate that about 41 percent of all deer in the original CWD core area have CWD-resistant genes, which they will pass on to offspring. If natural selection follows its normal progression, deer that are CWD-resistant should become dominant in a few hundred years. That’s good news to hunters like Grabski.

“This evolutionary change could take place in an area with low infection rates in as little as 250 years,” Grabski added. “In an area of high infection, the process will be accelerated, and most deer could be CWD-resistant in as little as 50 years.”

The implications for CWD management are enormous. Those who still advocate harvesting large numbers of deer to try to eradicate CWD and/or for CWD testing will undoubtedly take out CWD-resistant deer from the wild, slowing the process of natural selection. In the end, it’s probably best to leave CWD management to Mother Nature.
 

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Discussion Starter #9
I agree I hope there is a lot of work going into to this to nail it down and to come up with a plan and tools to come up with a plan. Maybe someone on here can let us know.
 

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I agree I hope there is a lot of work going into to this to nail it down and to come up with a plan and tools to come up with a plan. Maybe someone on here can let us know.
I don't think there will really be anything to do with wild populations. Mother nature will naturally do it over time.
 

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If this is true, the question is, in whose lifetime?
 

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If this is true, the question is, in whose lifetime?
From the article.

“This evolutionary change could take place in an area with low infection rates in as little as 250 years,” Grabski added. “In an area of high infection, the process will be accelerated, and most deer could be CWD-resistant in as little as 50 years.”
 

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Discussion Starter #13
Does anyone know what the pgc's position is on the genetic approach . I live in the CWD area 2 near Bedford and I hear they are planning on bringing in sharpshooters in the next few months. I hope they take the time to consider if that is the correct approach.
 

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RSB mentioned this on another thread. They did sharpshooters in areas directly where the most was found an if your from Bedford you know that is a hot spot where many was affected and found. So a guy like myself that hunts in Monroe township but still in the dma isn't taking out the ones mainly where the initial findings was. Keep in mind when they created the DMA was for a purpose of trying to keep in contained as much as possible. Around 3 or so years ago when this first came out they was established and made a broad perimeter of the area. The following year they found more close to the perimeter and made it larger on the west side pushing it more in to Somerset county to rt. 160. They are really doing the best they can on a uphill battle.
 

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From the article.

“This evolutionary change could take place in an area with low infection rates in as little as 250 years,” Grabski added. “In an area of high infection, the process will be accelerated, and most deer could be CWD-resistant in as little as 50 years.”

If I recall correctly, although about 49% of the deer sampled appeared to have the resistance gene, a few of those deer with the resistance gene also acquired CWD but showed delayed symptoms and they lived longer. There also seemed to be some trends related to ages in that the gene seemed to be more prevalent in older deer. I suspect this is due to the fact that younger deer without the gene die before reaching the older ages.

The real problem with trying any type of genetic manipulation of the population is that all harvest, whether it be from sharpshooters or hunters would need to stop in order to ensure that CWD kills the deer that don't have the gene and the maximum number of deer that have the resistance gene survive to continually reproduce. Any harvest would probably greatly increase the time needed to introduce the necessary number of genes to allow the herd to survive from CWD.

This also assumes that CWD does not evolve to eventually affect these resistant deer. One question is does it evolve?
 

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Discussion Starter #16
One way to help nature along might be to capture as many deer as possible in a hot spot area.

Test all of the deer for the genetic resistant gene

Tag and release all deer with the gene after tagging them with a tag hunters and biologists could see

Kill all the deer without the gene and test them for cwd

Repeat the above at least once per year

If a test is developed for cwd that can be used on live deer, all of the deer without the disease could be released.

By doing this, the deer with the good genes would be saved and would start to turn the hot spot into a cwd free area that could expand naturally from what was once the problem area.

The deer with the tags should not be shot by hunters so they can continue to produce new deer with the good genes in the wild. If they are shot or are otherwise killed they should be tested to confirm they have not developed the disease.

An option would be to take all off of these deer to a large fenced area where the entire population could be monitored. There should be several former deer farms available. This may be the best way to study if the disease evolves in gene resistant deer because more of the deer would reach old age. If the deer are tagged and not shot, many would also get to old age in the wild. By doing some GPS monitoring they could be recovered and tested.

To me, something like this plan is preferable to sharpshooting all deer in the hot spot. It gives more hope for a long term solution and should greatly increase the amount of knowledge me have about this disease. There may be some increased risk of the disease spreading from the released deer that later develop the disease but these deer would be checked each time the are caught so the risk would be small.
 

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WIZ, prion diseases to have a propensity and history of mutating to cross species lines. I can see no reason to have any confidence that there will be CWD resistant deer, we aren't sealing with a bacteria or a virus, we are dealing with a protein that cannot be killed and has a long history of mutating. I
have yet to read anything that says some deer will become resistant that is accepted science. The very thought of capturing wild deer and testing them in such numbers to even make an experiment worthwhile is dubious at best. The most common prion diseases are Scrapie and Mad Cow in domestic animals and no one has figured our a way to eliminate it and it is easier to control the environment of domestic animals than wild ones.
 

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Discussion Starter #20
Prions mutate and so do deer genes. Over time the deer have mutated to resist the disease. It may have been hundreds or thousands of years for them to reach a point where the disease was under control.

My thought is that here has been some change that has upset the balance. Maybe it is the shipping of deer around the country that has made unnatural concentrations of diseased deer where were were none before or where there were few gene resistant deer. Maybe it is because we selectively shoot some age classes and that results in having more diseased deer around longer to infect others. Maybe it is because of farming practices that leave no food in large fields so deer concentrate around food plots and contaminate the area. Maybe it is because people are more frequently moving deer they have shot in an infected area and taking it to an uninfected area to discard the spinal cord and brain. All of these things have taken place more frequently in the last 50 years.

With mad cow, they shoot all the animals in the pen. I have not heard if there are any resistant cows that are similar to those found in deer. Cows have not run wild for a very long time so maybe their chance at dealing with mad cow naturally has been lost.

We will not be able to stop this problem by shooting all the deer in an infected area. That will stop nature from controlling the genetically resistant deer from gaining dominance over the disease. I have not heard anyone say that this shootng policy will eliminate the disease. I did see in the paper posted earlier in this thread that it will be controlled in 50 to 250 years if no steps are taken.

Of course we can afford to do this. You could put the deer is an existing fenced area and monitor to see what is really happening. However that would not address the hotspot. If the deer are not separated with only the good ones returned, the effect would be the same as shooting them all in place.

I have not heard how many deer they are planning to shoot but I do know that at one time they trapped deer in Michigan and Texas and shipped them around the country for stocking. How did they get the elk back to Pa? We can afford to trap them in Bedford and ship them to a pen and back.
 
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