BIO: Synethetic DNA

Date: Sun Jan 23 2000 - 10:17:53 MST

>From The Sunday Times,

January 23 2000 BRITAIN

First artificial DNA can create new forms of life

Jonathan Leake and Roger Dobson

SCIENTISTS have made the world's first synthetic DNA - the molecules that
form the blueprint for life.

The breakthrough means that the first artificial organisms could be "born"
within two years and raises the prospect of humans redesigning whole
species, including themselves.

The DNA was created at the University of Texas where researchers have mapped
out the exact way it will be configured to create synthetic organism one
(SO1), the microbe destined to be the world's first man-made creature.

"We are synthesising DNA to create the first synthetic organism," said
Professor Glen Evans, director of the university's genome science and
technology centre. "SO1 will have no specific function but once it is alive
we can customise it. We can go back to the computer and change a gene and
create other new life forms by simply pressing a button."

The researchers are planning to create a series of designer bugs, with
super-efficient mechanisms for infecting target tissues such as cancer
tumours - and then killing them. Some would infect the human gut to produce
vitamin C.

Critics, however, have warned that the scientists risk unleashing a microbe
master race with increased powers to infect humans and wildlife.

The researchers' success lies in having found a way to create long chains of
DNA. Such chains are made up of four types of molecule which join up in
twosomes known as "base pairs". The base pairs then link to form a ladder
that twists into the famous DNA double helix.

In nature, one chain of DNA can contain hundreds of thousands of base pairs.
Until now, however, scientists have found it impossible to join together
more than 100.

Evans's team has broken this barrier with a technique that first creates
short chains of DNA and then joins them together in a controllable way.

The scientists are close to achieving chains that contain 100,000 base
pairs - enough to form the basis for simple life forms.

The design for SO1 is based on analyses of the genes of other small
bacteria. Genes are the functional units of DNA, each one being responsible
for creating a protein essential to processes such as respiration.

Evans plans to copy the vital genes from each bacterium, select the best and
join them together. In nature all DNA also contains "junk genes" with no
function but Evans plans to omit these - possibly making SO1 the most
efficient organism that has lived.

The work to create SO1 is complex but the test of success will be simple.
Can SO1 feed and reproduce? If so, then Evans will indeed be celebrating new
life. Opponents, however, will regard such an event very differently.

Tony Juniper, policy and campaigns director of Friends of the Earth, said
the bugs could present a serious threat to human health and the environment.
He said: "Scientists have already unleashed genetically modified organisms
and we are now seeing the damage they can do. Playing God by creating
entirely new life forms could have very serious consequences which should be
publicly and fully debated."

Others are less perturbed. Michael Reiss, a specialist in bioethics at
Cambridge University, said he would become concerned only if such life
became sentient. "In the 19th century people thought there was some vital
essence to life and there was real controversy when the first organic
compounds were made. My own view is that DNA is just an extension of that
process," he said.

Evans believes that man will one day be able to create complex life forms.
For now, however, the first benefit could be simpler - the end of the
vitamin pill. "Humans need but cannot make vitamin C because we lack one
particular enzyme," he said. "If we put that enzyme into one of our
artificial organisms and drink it, the bug will live in our guts making
vitamin C for ever."

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