- LONDON, June 10 (Reuters) - A Franco-British team of scientists has
cracked the genetic code of tuberculosis, an infectious lung disease that
kills more people each year than malaria and AIDS combined. The team has
deciphered the entire 4,000-gene sequence, or genome, of the TB bacillus,
which should speed the development of new drugs and vaccines against the
chronic airborne ailment that has defied scientists' best efforts at eradication.
``I think it will be a landmark in the history of tuberculosis research,''
Dr Stewart Cole, one of the researchers, said in a telephone interview.
- ``We've identified all the genes and
predicted what quite a few of them are doing, so it opens up thousands
and thousands of new areas for people to do research in.'' It took the
scientists from the Pasteur Institute in France and Britain's Sanger Centre
more than two years to complete the joint project, financed by the Wellcome
Trust and reported in the science journal Nature on Wednesday. Tuberculosis
is not the first disease to be decoded. Scientists have already mapped
out the genome for Lyme disease and other bacteria, but the TB bacillus,
Mycobacterium tuberculosis, is the most sophisticated sequencing achievement
and one that could have far-reaching implications for public health.
- ``I personally think it is the most important
one to date,'' Cole said, adding that sequencing the genome for malaria,
another infectious killer, would have similar significance. Douglas Young,
a microbiologist at Imperial College School of Medicine in London, said
the history of the disease, together with the clues to conquering it, were
hidden in the genome. ``Thanks to Cole et al, we now have the sequence
of every potential drug target and of every antigen we many wish to include
in a vaccine,'' he said in a commentary in Nature. One third of the world's
population is infected with the TB bacillus. Three million people die of
the disease each year. It is particularly dangerous for HIV sufferers because
each disease speeds the progress of the other. TB accounts for nearly one-third
of AIDS deaths worldwide. Such is the scale of the epidemic that the World
Health Organisation (WHO) predicts that between 1998 and 2020, nearly one
billion more people will be infected, 200 million people will become ill
and 70 million will die unless controls are strengthened.
- New drug-resistant strains are emerging
and, in spite of the best efforts of the WHO, the disease has reached epidemic
proportions in many poor countries. After being nearly wiped out, it is
re-emerging in some rich countries. ``With the globalisation of communities
people are moving around the world more easily and more frequently. There
is an increasing likelihood that Westerners will get infected if they visit
developing countries and this will be imported inadvertently,'' Cole said.
The ground-breaking project removes much of the laborious preparatory work
for other scientists and pharmaceutical firms, allowing them to focus better
on their research. ``It will certainly lead to drug companies and vaccine
designers taking more interest in the subject because they have all this
free data there at their disposal,'' Cole said. ``If they've got some clever
ideas they can just apply them now.''