truthout http://www.truthout.org/issues_05/071505HB.shtml
Original
http://news.independent.co.uk/world/science_technology/article299270.ece
Gene 'Maps' Show Way to Beat Killer Diseases
By Steve Connor
The Independent UK
Friday 15 July 2005
Three of the most devastating diseases of the developing world
could soon be eradicated after a breakthrough in understanding how they
are programmed to be human parasites.
Scientists have decoded the genetic blueprints of the parasitic
microbes responsible for African sleeping sickness, Chagas disease and
Leishmaniasis, which collectively affect up to 30 million people and
endanger the lives of a further 500 million.
Knowing the precise sequence of genetic "letters" that make up the
alphabet of the microbes' genes should now allow scientists to design
effective drugs and vaccines against the three killers. At present,
there are no vaccines or cheap, effective remedies against any of the
parasites, each transmitted by the bites of different insects in some
of the poorest countries.
More than 250 scientists from 21 nations - including the Wellcome
Trust Sanger Institute in Cambridge - helped in the £18m project to
decode the genomes of the three single-celled organisms belonging to a
family of parasites called trypanosomatids.
Professor Najib El-Sayed, leader of a research team from the
Institute for Genomic Research in Rockville, Maryland, said: "Thanks to
these studies, scientists are now much closer than they were five years
ago to developing effective drugs against these terrible diseases."
African sleeping sickness is caused by the parasite Trypanosoma
brucei, which is transmitted by the tsetse fly. It affects many
countries in sub-Saharan Africa and causes fevers, headaches, joint
pains and itching, followed by debilitating infection of the brain and
central nervous system.
Chagas disease is caused by Trypanosoma cruzi, which is transmitted
in the bite of a blood-sucking bug that thrives in the cracks and
crevices of poor housing in South America. Over many decades, patients
suffer severe damage to their internal organs, including the heart and
intestines. The final microbe to be decoded is Leishmaniasis, which is
transmitted in the bite of tiny sand flies. It causes severe skin
disfiguration as well as long-term disease, fever and weight loss.
The research, in the journal Science, shows that each parasite has
a set of some 6,200 "core genes" arranged in a similar way that appear
to play a vital role in the function of the parasitic organisms. Peter
Myler, from the Seattle Biomedical Research Institute said the mapping
aids design of specific drugs that target one or all of the three
parasites. "Initially, we believed the gene organisation among the
parasites would be different, but 70 per cent of the genes occur in the
same order," Dr Myler added.
"The core genome of all three is very similar, with the differences
mainly at the end of the chromosomes. So this tells us if we focus on
the genes that are the same in all three, but different from humans, we
have the potential to develop a class of drugs that can target all
three diseases." Decoding the genes of the three parasites will allow
scientists to understand how they infect people, how they cause human
disease and why they are carried and transmitted by different insects.
George Cross, of the Rockefeller University in New York, said that
existing drugs may even be useful against the diseases after the
biology of the parasites was better understood through the analysis of
their genomes.
"Because of their distinct evolution, trypanosomes present a
plethora of potential drug targets and potential drugs are almost
certainly languishing in the chemical libraries of pharmaceutical
companies," Dr Cross said.
Three of the most devastating diseases of the developing world
could soon be eradicated after a breakthrough in understanding how they
are programmed to be human parasites.
Scientists have decoded the genetic blueprints of the parasitic
microbes responsible for African sleeping sickness, Chagas disease and
Leishmaniasis, which collectively affect up to 30 million people and
endanger the lives of a further 500 million.
Knowing the precise sequence of genetic "letters" that make up the
alphabet of the microbes' genes should now allow scientists to design
effective drugs and vaccines against the three killers. At present,
there are no vaccines or cheap, effective remedies against any of the
parasites, each transmitted by the bites of different insects in some
of the poorest countries.
More than 250 scientists from 21 nations - including the Wellcome
Trust Sanger Institute in Cambridge - helped in the £18m project to
decode the genomes of the three single-celled organisms belonging to a
family of parasites called trypanosomatids.
Professor Najib El-Sayed, leader of a research team from the
Institute for Genomic Research in Rockville, Maryland, said: "Thanks to
these studies, scientists are now much closer than they were five years
ago to developing effective drugs against these terrible diseases."
African sleeping sickness is caused by the parasite Trypanosoma
brucei, which is transmitted by the tsetse fly. It affects many
countries in sub-Saharan Africa and causes fevers, headaches, joint
pains and itching, followed by debilitating infection of the brain and
central nervous system.
Chagas disease is caused by Trypanosoma cruzi, which is transmitted
in the bite of a blood-sucking bug that thrives in the cracks and
crevices of poor housing in South America. Over many decades, patients
suffer severe damage to their internal organs, including the heart and
intestines. The final microbe to be decoded is Leishmaniasis, which is
transmitted in the bite of tiny sand flies. It causes severe skin
disfiguration as well as long-term disease, fever and weight loss.
The research, in the journal Science, shows that each parasite has
a set of some 6,200 "core genes" arranged in a similar way that appear
to play a vital role.
-------
(In accordance with Title 17 U.S.C. Section 107, this material is
distributed without profit to those who have expressed a prior interest
in receiving the included information for research and educational
purposes. t r u t h o u t has no affiliation whatsoever with the
originator of this article nor is t r u t h o u t endorsed or sponsored
by the originator.)
|
