Prion/Mad Cow questions

Factual Questions
1

  1. Is it theorized that the Mad Cow prions are all decended from a single “mother” prion, or is it likelier that several “populations” formed independantly?

  2. A coworker of mine speculates that a factor in the Mad Cow prion arising is that cows, an herbivorous animal, were fed meat-based feed. It certainly was a factor in it spreading, but has anybody theorized that it was or is a factor in the initial creation of the prions?

2

Don’t have the time myself (…maybe someone else ?) to research and answer in full, sorry. However, I believe this link should offer as much information as most people might need. As I understand it, this was the definitive analysis of what happened and how:

The BSE Inquiry

When I tried, the term ‘Prions’ returns 17 different results on the web site.

3

I didn’t read the link with all the hyperlinks, so I may have missed something, but your question assumes something that isn’t so, AFAIK: prions do not reproduce. They have no genetic material. They are a type of protein which every one has. The disease is caused by defective prions. What causes the prions to become defective is, so far as I know, unknown. I’m sure if you make a search for prions + BSE or prions + Mad Cow Disease, or prions + Jacob-Crutsfield (sp?) you will find plenty of info.

4

Let me add a little to my last post. Africans were getting the same disease, but called kuru, by eating monkey brains. The protein, when not defective, is not called prions. Once the protein becomes defective, it sends out chemical signals corrupting the other proteins.

It’s amazing that the disease is caused by eating prions. They have to escape the digestive system and the body’s own defenses. In most cases, the disease is not manifested until 20 years later. So, you have all these people living with swords over their heads.

5

There’s some pretty good info in this thread on prion diseases. There are also some interesting links.

The upshot: Prions are a class of proteins that become pathological when “stuck” in their folded forms. They do not reproduce, but they are believed to cause non-pathological prions to become stuck (and pathological). Proteins in their folded state are relatively stable–it may be that additionsal chemical bonds in the pathological prions stabilize them further against heat and chemical action. They can easily survive the digestive system, boiling, and limited burning.