h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

I would like to recommend this http://www.h2g2.com/A480638 article which is about "Prions".

Prions are the little particles of protein that cause diseases like CJD in humans, scrapie in sheep and BSE (mad cow disease) in cows. They cause a lot of other diseases too and the way they do it is completely unique, as far as we know. I thought the subject was fascinating and I hope you will too.

Please have a read and let me know whether it's ok, or should I edit or add to it. Thank you.

Well, I found this article very informative, and I highly reccommend it for inclusion in the edited guide

-The Admiral 8)
[URL removed by moderator]

Seconded. Seems like a good summary of research to date. I know you're worried about length but I think at the moment you've got it about right. I did think about suggesting you add a reference or two for further background reading but I can't quite convince myself that's necessary here.
Fascinating and topical topic of which we are certain to hear more over the coming years. I'd certainly like to see it take its place in the Edited Guide.

Thanks The Admiral and Metal Chicken! I'm glad you don't think it's too long. I know there's no rule about length of articles, but I didn't want to put people off reading this by making it huge. I thought of putting in some site links so people could find further information, but when I put links in my other articles, the editors stripped them out so I thought it was probably a waste of time.

Wonderful job!
Well written and a good review of the subject matter.
I, however, being a scientist myself, think references are always good things to include

*Agrees with all of above comments*

Thank you very much Ariel and Krans. I subscribe the old-fashioned idea that the customer is always right, so I'll put those reference/links in as you suggest. Anyway, now that I come to think about it, the poor old editors have to check these things for accuracy so even if they do end up stripping out the references, they might still find them useful. I expect I'll do it tomorrow. The site is so slow at the moment it's difficult to get anything done. I'll let you know when the job's finished.

If I only had earlier known what Prions are! -- I really thought of a pop group or such and neglegted this thread. What an entry! No doubt this one /is going/ to go into the Guide, and I hope the Sub-Ed will cross-reference it with the entry on Cannibalism.

Hey Bossel! Brilliant idea! I hope they do too

I've added 3 references in the form of footnotes that you can click on to take you off to the web sites. Any further comments and suggestions are welcome . . . please. Thank you.

Thanks for including the refs.... its nice to see my old alma mater (U of Chicago) geting a bit of press!
Love the idea of the cross ref to cannibals (shiver).... hope the eds take you up on it.. uhm.. the cross ref I mean.
cheers-
Ari

Hi Sal,

First of all, I'd like to add my congratulations on this excellent entry to the ones above.

A couple of small clarifications, though:

You state that prion diseases can be inherited, and that therefore there is a genetic component. Whilst transmission from mother to infant has been demonstrated, are we sure that this necessarily means a genetic component? After all, mother and infant share a lot of bodily matter which is not genetic.

Secondly, you state baldly that vCJD "is acquired from eating beef". I had thought that the current position was that infected beef *was the most likely source*, but that many scientists still believe otherwise. A large percentage also believe that the infection is only passed in tissue from, or from near, the central nervous system.
I should declare that, as some of my family are in the beef farming industry, I have a vested interest in making sure that the article is rigorously balanced!

Churlishness aside, this is an important and well-written study.

I have a depressing feeling that the current countermeasures (including the slaughtering of older cattle) will only result in disguising the disease, not eradicating it. If (for instance) all people for ten generations were killed off at 40, the incidence of Alzheimer's would drop to virtually zero (because it's overwhelmingly an illness of the old), but that doesn't mean it would have "gone away" in any meaningful sense. Maternal transmission may make the same thing true of BSE/vCJD.

This whole saga has a chilling parallel in Kurt Vonnegut's sci-fi story "Cat's Cradle", where an allotrope of ice is discovered which freezes above room temperature - and which catalyses surrounding water to form the solid; strongly analogous to the way prions appear to work. One crystal of this "ice-9" dropped in the ocean heralds, basically, the end of life on the planet. Scary.

Wonderful article! I hate to say anything critical at all, but there are a few things that I think you should mention:

1) Your definition of a prion states that it's a protein and approximately how large it is, but it doesn't say anything about it causing disease or being infectious. I know that these facts are stated almost immediately after, someone reading the first sentence might get the impression that most proteins are prions. This is a bit of a picky objection, but you might want to be just a bit clearer in the beginning.

2) You might want to mention that there have been several confirmed cases of prions being transmitted surgically. I remember reading about a group of patients who undergoing brain surgery for epilepsy who were thought to be at risk because the surgical tools used in the operations had been previously used on a patient who was later found to have a prion-caused neurodegenerative disease. The standard sterilization procedures actually aren't enough to destroy proteins, so there was a great deal of concern over whether or not the patients had been exposed. I believe that those patients are still being watched for signs of illness. There was also a case of a woman who contracted a prion though a corneal transplant, although this wasn't found until the postmortem examination. I think she became demented and died; I think she was in her late 20s or early 30s when this happened.

Although you might want to include these points in your article, they're probably not necessary, and it's well-worth being put into the Guide as is. Good luck!

[bows respectfully]

--Caledonian

Excellent article, and understandable by non-scientific types!

I hadn't realized that kuru was a prion problem, although I was aware of the cannibal link. It also appears in non-cannibal areas - I remember an incident in the Far East about 1968 which was attributed to pork.

Would it be be worth mentioning the difficulty of destroying prions? There has been some articles in the UK press over the last few days about hospitals using disposable tools for certain operations because normal sterilizing won't "kill" prions.

Again, enjoyable reading, and very topical, and unfortunately likely to be topical for several years!

Ariel, was Prof Prusiner one of your tutors? Wow. I'm impressed!


Hi Global Village Idiot

Thank you for your kind words.

I understand your concern and that the main focus of your attention is the BSE problem but this article is more generally about the behaviour of prions.

The clarification you require:

1) The transmission from mother to infant (I'm guessing you mean between cow and calf) you refer to wasn't actually mentioned in this article so that wasn't the basis for the argument. If you read the section under the heading "The Road to Discovery", you'll see that I described the studies involving people with GSS and then more generally, referred to point mutations found in the genes of families with other inherited prion diseases. Then I went on to describe the experiments carried out on transgenic and non-transgenic mice. The evidence in those cases did seem pretty clear.

2) Again, I understand your concern. I was at pains to make it clear, throughout the article, that a lot of research still has to be done. There does seem to be a wide consensus among the scientists that beef is the source of vCJD though. Some of the studies concentrated on the species barrier and strain typing and they found that the BSE prion could be transmitted to a lot of other species including pigs, monkeys and us.

I didn't go into cow anatomy when I said that new variant CJD is acquired from eating beef because it seemed sufficient to just say beef was the source. I did mention earlier in the article, under the heading "The Diseases", that prions collect at certain sites in the body. I didn't write the article as a warning to people who eat beef, but if that had been the purpose of the article, then I would have needed to add all sorts of other information about slaughter house practices and the way some do and some don't follow proper procedures to ensure that no potentially infective material is left on the carcass. I think the article would have become unbalance if I'd concentrated too much on BSE.

I think perhaps the BSE crisis might be a suitable subject for an article in its own right. What do you think?

I agree with you about the slaughtering of cows at 30 months. I always thought that was a bit silly. Well, in fact I thought it seemed like a not particularly clever trick to hoodwink people into thinking the problem was being dealt with and it was all under control.

Sal

Thanks Caledonian and BuskingBob.

It's taken me over an hour and a half of messing about to post that last message to Ariel and Global Village Idiot. I'll answer your messages a little bit later if you don't mind. I'll speak to you soon - my computer, my ISP, the internet and h2g2 willing!

Sal

Hi Sal,

Thanks for getting me straight - I hadn't had enough cups of coffee ths morning when I read your article and somehow gave myself the impression that you were implying a genetic component in BSE/vCJD. Your article clearly doesn't say that. so I'll withdraw gracefully

An interesting result of the genetic research might be the danger of contracting 'old' CJD (or GSS or the others) from, say, a transfusion or transplant from a genetic sufferer who isn't yet showing any symptoms. Yet another thing to worry about .
I'd bet that within ten years, people will have to undergo 58 sorts of genetic test before they're considered as donors for anything - and what implications will that have for blood transfusion, kidney transplants and all the rest? All because failure to do so will trigger an expensive lawsuit...

I certainly agree that the mechanism and theory of prions, as a topic in its own right, is worthy of an entry - its an amazing fertile area at the cutting edge of science - and this should be it. The idea of writing a separate entry on the BSE crisis and vCJD is an interesting one, though there is the danger it could go out of date quite quickly, and I don't know if you'd ever get everyone to agree it was 'impartial'.

Anyway, I look forward to this article going live, because if Peer Review is anything to go by, it's going to cause some pretty lively discussion!

Congrats again on a brilliant piece.

GVI

Hi Caledonian and BuskingBob. I wonder how long it'll take to post this when I've finished it. Ah well, here goes.

Caledonian:

1) You could've knocked me over with a feather with this one The first sentence was very short. In the very next sentence I said that it was an infectious particle. It couldn't get very much closer to the beginning. I think the only danger that a reader might get the wrong impression, is if they only read the first sentence and then read no further.

2) I did mention briefly, under the heading "Transmission", that doctors have sometimes accidentally infected patients with a prion disease by using contaminated surgical instruments and by carrying out procedures such as corneal transplantation. Perhaps I should stress what tough little devils prions are to destroy. That section might be the best place to slot it in too.

BuskingBob:

1) I'd be interested to hear more about the kuru amongst non-cannibals and the link with pork.

2) You and Caledonian have both mentioned the difficulty of destroying prions so I'll consider that point seconded.

3) The thing in the news has been about using disposable instruments to perform tonsillectomies. I mentioned that sheep could be tested for scrapie by examining their tonsils ('ok Flossie, just say "aaah" for me').

Thank you both for your input. I'll let you know when I've added the bit about how difficult it is to destroy prions.

Sal

Heehee...nah, but I got to meet him at a recent symposium. I do ears not prions
Lovely work.... i look forward to reading more from you!
cheers-
Ari

Ok Caledonian and BuskingBob, I've added a paragraph on the difficulty of destroying prions, under the heading "Transmission". To save you going over to read the article again, this is the paragraph:

"Prions are extraordinarily robust. Normal proteins are easily broken down by the body's own enzymes. Prions are not broken down by the body's enzymes or by the type of acid found in the gut (which is fairly strong). Bleach and heat leave it sufficiently intact to remain infectious. It has been shown that it can remain infectious after heating to 360 degrees C for an hour. Ultra violet radiation does not damage it significantly. In one experiment, infective tissue was buried in soil for three years and was still infectious when recovered. Until quite recently, doctors were unaware of exactly how resilient and infectious prions are. No wonder some unfortunate patients were accidentally infected by inadequately sterilized instruments."

Thanks for pointing out the gap. I hope it meets with your approval

Global Village Idiot,

I agree with you on the following: 1) You are graceful. 2) I did read an article that highlighted the fears of inherited CJD and GSS being transferred by blood transfusion. 3) You could be right about the possibility of a balanced article on BSE/vCJD. Shame about that because it would be interesting.

Ariel,

What sort of symposium do you find an ear person and a prion person attending?

Sal