Scientists Try to Create New Life
By PAUL RECER 11/21/2002 16:01:51 EST
WASHINGTON (AP) - By modifying a simple microbe, scientists hope to create a new
form of single-cell life that could lead to new and cleaner energy and perhaps play a
role in biological warfare. But there are safety and ethical concerns in this new world of
biology, experts say.
A group led by J. Craig Venter, director of a private program that mapped the human
genome, has received a $3 million Department of Energy grant to make a new type of
bacterium using DNA manufactured in the lab from basic chemicals.
The goal, said Venter, is to build a bacterium that is capable of making hydrogen that
could be used for fuel, or to develop a microbe that could absorb and store carbon
dioxide, thus removing a surplus of that greenhouse gas from the atmosphere.
Along the way, said Venter, scientists will learn on a molecular level the minimum
genes a cell needs to thrive and reproduce and how to artificially make those and other
genes.
"This is true basic science," said Venter. "Even though we've found all those genes in
the human genome, we can't understand the most basic simple cell yet. That is what
is driving this."
Some experts worry that by learning how to artificially create the basic genes
essential to life, even in a fragile, obscure microbe, scientists may open a new door to
biological hazards and, perhaps, put a new weapon into the hands of terrorists.
"We have to be very careful about controlling the purposes of this research," said
Kathy Kinlaw, an executive in the Center for Ethics at Emory University. She said that
science will ultimately achieve what Venter is attempting, but that there must be
careful oversight to prevent the technology from being misused.
The DOE grant was given to the Institute for Biological Energy Alternatives, a company
founded by Venter. The organization now has 10 scientists, including Nobel laureate
Dr. Hamilton O. Smith, an expert on genetic science and famed for his skill in handling
DNA in the laboratory. Eventually, IBEA will grow to a scientific staff of about 25.
Venter said the plan is to extend work that he and others started in 1995 at the
Institute of Genomic Research. Researchers there sequenced the genes of a
bacterium called Mycoplasma genitalium, one of the simplest microbes known with
only one chromosome and 517 genes. By contrast, humans have about 30,000 genes
and 23 pairs of chromosomes in each cell.
Once the normal gene complement of M. genitalium was identified, the researchers
began systematically removing genes to determine how many were essential for life. In
1999, they published a paper that narrowed the minimum needs of M. genitalium to
265 to 350 genes.
Under the new grant, Venter said the researchers will use basic chemicals to
snythesize the DNA in M. genitalium's single chromosome. They will then use
radiation to kill the chromosome in a normal bacterium and replace it with the
lab-made DNA.
Venter said the cell will retain some of its functioning parts, such as enzymes and
RNA, but that all of its genetic structure will be synthetic.
"The description of this being a modification rather than making new life is probably
correct," said Venter. "There is a philosophical question of how many genes can you
change in an organism" before it becomes a new life form.
Dr. Clyde Hutchison of the University of North Carolina, a microbiologist who was part
of Venter's team at TIGR, said M. genitalium is a good microbe to use because it is so
simple and poses no safety concerns.
"It is very fragile and really can't live outside the laboratory," said Hutchison. He said
the microbe normally lives in the genital tract of humans, but causes few health
problems.
The microbe lacks the tough cellular wall of most bacteria and is a total parasite,
depending on its host to make even the most basic amino acids, he said.
In theory, a new understanding about the basic workings of a cell could help develop
new bioweapons, said Venter, but the plans call for withholding some key information
his group discovers.
"We will be cautious about how and where we disclose new techniques," he said. "We
don't want a group of crazies to deliberately make something that is harmful."
Venter was the head of Celeria Genomics, a private group that sequenced the human
genome at the same time as an international, government-supported project. The two
groups published their findings in separate journals and were jointly honored in a 2000
White House ceremony. |
