Susceptibility and miasmatic history
Posted: Sat Mar 12, 2005 10:07 am
Is the following article interesting to those involved in present
discussion which I must admit is over my head though quite enjoying it,
Jean
Europe's plagues helped halt AIDS
Russell Jenkins
March 12, 2005 LIFE was nasty, brutish and short when waves of plague
swept across Europe right up to the 18th century.
Scientific research now suggests, however, that the terrible suffering
of those generations means a significant proportion of modern Europeans
are now resistant to AIDS.
A study by two British biologists published in the Journal of Medical
Genetics suggests about 10per cent of Europeans have this protection as
a direct result of the series of plagues that swept across the continent
from the Middle Ages onwards.
Biologists have known for some time that people carrying a genetic
mutation known as CCR5-delta32 remain free of the deadly disease. The
mutation prevents the human immunodeficiency virus from entering the
cells of the immune system.
It has always been puzzling that the strains of HIV that have swept
through Africa have had so much less effect in Europe.
The new theory suggests the CCR5 mutation, which prevents HIV from
entering the cells of the immune system, was a by-product of the
European plagues. The proportion of people carrying the natural
resistance rises dramatically in Europe and particularly in Scandinavia,
where the figure of those with resistance is 14-15per cent.
But the mutation is relatively low in countries bordering the
Mediterranean and not found at all in sub-Saharan Africa, Asia or among
native Americans.
Christopher Duncan and Susan Scott of the University of Liverpool's
School of Biological Sciences suggest the natural protection from HIV
can be attributed to the history of the plague. They have put forward a
matrix showing how the frequency of genetic mutation rises with each
stage of plague outbreak from the Black Death in 1347 to the Great
Plague of London (1665-66) and beyond to the Plague of Copenhagen more
than half a century later.
Using a computer model, they demonstrate how the pressure of natural
selection increases the number of those carrying the resistance from
about one in 20,000 when plague first devastated Europe during the
mid-14th century, to one in 10 300 years later.
Professor Duncan and Dr Scott, authors of The Return of the Black Death,
published last year, insist these plagues were not bubonic, but
epidemics of viral haemorrhagic fever that used the CCR5 receptor as the
"entry port" into the immune system.
These lethal haemorrhagic fevers - whose modern version is Ebola fever -
are believed to have occurred as far back as antiquity.
They were recorded in the Nile Valley from 1500 BC, Mesopotamia
(700-450BC), Athens (430BC), the plague of Justinian (AD 541-700) and
the plagues of the early Islamic empire (AD 627-744).
If the plague struck a village and killed half the population, those
with the natural resistance would become a higher proportion of the
survivors.
Professor Duncan dismisses theories that resistance to AIDS can be
attributed to smallpox or bubonic plague. Bubonic plague is a bacterial
disease, not a virus, and cannot be blocked by the mutation.
He is less sure that his work will have any practical impact on medical
research and is not hopeful the genetic mutation can be reproduced
artificially to create protection.
/The Times/
discussion which I must admit is over my head though quite enjoying it,
Jean
Europe's plagues helped halt AIDS
Russell Jenkins
March 12, 2005 LIFE was nasty, brutish and short when waves of plague
swept across Europe right up to the 18th century.
Scientific research now suggests, however, that the terrible suffering
of those generations means a significant proportion of modern Europeans
are now resistant to AIDS.
A study by two British biologists published in the Journal of Medical
Genetics suggests about 10per cent of Europeans have this protection as
a direct result of the series of plagues that swept across the continent
from the Middle Ages onwards.
Biologists have known for some time that people carrying a genetic
mutation known as CCR5-delta32 remain free of the deadly disease. The
mutation prevents the human immunodeficiency virus from entering the
cells of the immune system.
It has always been puzzling that the strains of HIV that have swept
through Africa have had so much less effect in Europe.
The new theory suggests the CCR5 mutation, which prevents HIV from
entering the cells of the immune system, was a by-product of the
European plagues. The proportion of people carrying the natural
resistance rises dramatically in Europe and particularly in Scandinavia,
where the figure of those with resistance is 14-15per cent.
But the mutation is relatively low in countries bordering the
Mediterranean and not found at all in sub-Saharan Africa, Asia or among
native Americans.
Christopher Duncan and Susan Scott of the University of Liverpool's
School of Biological Sciences suggest the natural protection from HIV
can be attributed to the history of the plague. They have put forward a
matrix showing how the frequency of genetic mutation rises with each
stage of plague outbreak from the Black Death in 1347 to the Great
Plague of London (1665-66) and beyond to the Plague of Copenhagen more
than half a century later.
Using a computer model, they demonstrate how the pressure of natural
selection increases the number of those carrying the resistance from
about one in 20,000 when plague first devastated Europe during the
mid-14th century, to one in 10 300 years later.
Professor Duncan and Dr Scott, authors of The Return of the Black Death,
published last year, insist these plagues were not bubonic, but
epidemics of viral haemorrhagic fever that used the CCR5 receptor as the
"entry port" into the immune system.
These lethal haemorrhagic fevers - whose modern version is Ebola fever -
are believed to have occurred as far back as antiquity.
They were recorded in the Nile Valley from 1500 BC, Mesopotamia
(700-450BC), Athens (430BC), the plague of Justinian (AD 541-700) and
the plagues of the early Islamic empire (AD 627-744).
If the plague struck a village and killed half the population, those
with the natural resistance would become a higher proportion of the
survivors.
Professor Duncan dismisses theories that resistance to AIDS can be
attributed to smallpox or bubonic plague. Bubonic plague is a bacterial
disease, not a virus, and cannot be blocked by the mutation.
He is less sure that his work will have any practical impact on medical
research and is not hopeful the genetic mutation can be reproduced
artificially to create protection.
/The Times/