Posted on 03/10/2005 3:11:16 PM PST by Pyro7480
Medieval Plague May Explain Resistance to HIV
LONDON (Agence de Presse Medicale) - The persistent epidemics of hemorrhagic fever that struck Europe during the Middle Ages provided the selection pressures that have made 10 percent of Europeans resistant to HIV infection, according to a UK study.
A mutation called delta-32 in the cellular receptor dubbed CCR5 protects against HIV infection, and is found more often in Europeans than other populations.
Scientists have previously suggested that the genetic mutation became common because it protected people against the Black Death or smallpox epidemics, while those with normal CCR5 were wiped out.
But researchers at the University of Liverpool in England said computer modeling, based on the changing demographics of Europe from 1000 to 1800 AD, showed how hemorrhagic fever forced up the frequency of this mutation from 1 in 20,000 at the time of the Black Death to values today of 1 in 10.
The researchers note in the Journal of Medical Genetics that lethal, viral hemorrhagic fevers were recorded in the Nile valley from 1500 BC and were followed by the plagues of Mesopotamia (700-450 BC), the plague of Athens (430 BC), the plague of Justinian (AD 541-700) and the plagues of the early Islamic empire (AD 627-744).
The European plagues from 1347 to 1665 were also a continuing series of hemorrhagic infections caused by a virus that used the CCR5 as an entry port into the immune system, the researchers explain.
Although plague passed its peak after the Great Plague of London in 1665, the researchers said it did not disappear completely.
Professor Christopher Duncan, from the University's School of Biological Sciences, added: "Hemorrhagic plague did not disappear after the Great Plague of London in 1665-66 but continued in Sweden, Copenhagen, Russia, Poland and Hungary until 1800.
"This maintenance of hemorrhagic plague provided continuing selection pressure on the mutation and explains why it (the CCR5-delta-32 mutation) occurs today at its highest frequency in Scandinavia and Russia."
SOURCE: Journal of Medical Genetics, March 2005.
A mutation called delta-32 in the cellular receptor dubbed CCR5 protects against HIV infection, and is found more often in Europeans than other populations.What do you want to bet this will be used as fodder for the "Whitey invented AIDS to kill the black man" crowd?
Even during the worst plagues there were always those who were immune. Those immune lived life like there was no tomorrow. They must have felt imortal.
Evolution in action bump....
There was a pretty detailed documentary on this subject that was aired not too long ago. It was a very involved study to make this discovery. It is odd that more hasn't been made of it.
Whoa, that is really bizarre.
Another example of scientific ignorance from Reuters. Shocking, but consonant with their political ignorance.
I am skeptical. Plague continued to be endemic and intermittently epidemic in China and India for most of the 20th century. Why would Europeans have developed the highest degree of resistance? Our knowledge of the medieval plagues in Europe compared to other areas of the old world is probably more related to documentation than to prevalence.
It could have been worded better. The frequency of the mutation rose because people without it died.
There is a flip side to that notion: ancestral exposure to disease had more to do with the rise of the African slave trade than did any innate sense of superiority to, or disdain for, black people. This ancestral exposure led to resistance to Malaria, the bane of American coastal plantations. Possessing workers that were immune to the disease was a great boon to indigo and rice planters. This genetic mutation is also responsible for Sickle Cell disease, though.
Of course, if it weren't for the increasing difficulty of acquiring indentured servants from Great Britain in the late 1600s, the much-more-costly African trade would never have been pursued to such degree in the first place.
When you consider the resistance that other genetic variations provide such as Tay-Sachs (resistance to tuberculosis) and sickle cell anemia (resistance to malaria), it makes sense that another variation could have become more common under the pressure of a plague.
There was a documentary concerning this on the History Channel last year.
That's the answer! A hardware-based firewall to block those ports.
"A mutation called delta-32 in the cellular receptor dubbed CCR5 protects against HIV infection, and is found more often in Europeans than other populations."
God will be called "RACIST!!" by the ACLU and GLAAD any day now.
There are a number of different modes of malaria resistance...most originate from SE Asia.
There is no such religion as Evolution. Only true believers.
I think this qualifies.
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