Biologist claims significant step towards artificial life
Pastor Dale Morgan
*Biologist claims significant step towards artificial life*
· Creation of synthetic chromosome announced
· Final step will be to put manufactured DNA in cell
* Alok Jha, science correspondent
* The Guardian,
* Friday January 25 2008
The biologist and entrepreneur Craig Venter has announced the creation
of a synthetic chromosome, knocking down one of the final hurdles to
building the world's first artificial life form.
Venter, best known for his race against publicly funded scientists in
the 1990s to sequence the human genome and more recently for hunting the
oceans for unknown genes, said the latest work was a "significant but
not final step" to creating new life.
In a paper published today in Science, Venter's team described the
synthesis of the entire genome of the bacterium Mycoplasma genitalium
from laboratory chemicals. The resulting DNA sequence has about 582,000
base pairs of genetic code in 485 genes. Venter said it was the largest
artificial sequence ever made, 20 times longer than any previous attempt.
The team at the J Craig Venter Institute (JCVI) in Maryland is working
on the final step to create life: transplanting the synthetic DNA into a
cell in the hope that it will "boot up" the cell and take control of its
growth and reproduction.
The scientists, led by Nobel laureate Hamilton Smith, began by building
long strands of DNA, each a copy of about a quarter of the whole M
genitalium genome. These were inserted into yeast cells, which stitched
together the strands to make clones of the whole genome, named M
genitalium JCVI-1.0.
The next step is to insert the synthetic chromosome into a cell, so that
it can reproduce and become a new life form. Venter's team has already
demonstrated that transplanting the genome of one type of bacterium into
the cell of another can change the cell's species, a process his team
will now use with the new synthetic chromosome.
Smith said that producing the artificial genome was like finishing the
operating system of a computer. "By itself, it doesn't do anything, but
when you install it on a computer, then you have a working computer
system. It's the same with the genome: the genome is the operating
system for a cell and the cytoplasm is the hardware that's required to
run that genome."
The work comes out of a larger JCVI effort to discover the minimum
number of genes needed for a life form. In its natural state, M
genitalium has 485 genes, 100 of which have been found to be
non-essential. Synthetic biologists want to use this information to
create the most efficient form of life possible, with the fewest genes
needed to allow the organism to grow, replicate and proliferate.
Venter said there were two main reasons for the work. "One is trying to
understand the minimal operating system of a cell and to understand
basic biology. If these experiments are successful we could enter a new
design phase of biology by actually constructing chromosomes of a
specific nature for a more specific purpose."
Stripped-down designer organisms have huge potential for creating
alternative sources of energy or tackling climate change by soaking up
carbon dioxide.
Venter has previously claimed that an artificial fuel-producing microbe
could be the first billion- or trillion-dollar organism. "When you think
of all the things that are made from oil or in the chemical industry, if
in the future we could find cells to replace most of those processes,
the ideal way would be to do it by direct design."
But Jim Thomas, of the Canadian bioethics organisation ETC group, called
for a moratorium. "In the absence of democratic oversight profiteering
industrialists are tinkering with the building blocks of life for their
own private gain."