THE GENOMICS AGE: How DNA Technology is Transforming
the Way We Live and Who We Are
by Gina Smith
In the history of mankind, few scientific phenomena have so profoundly
changed the human experience as will the revolution in the use of DNA
technology. Entertaining, informative, and written in plain English, The
Genomics Age explores how recent leaps in the understanding
of DNA offer astounding scientific promises -- and pose complex ethical
issues.
The Genomics Age probes the fundamental questions
borne of advances in applied DNA science: Can we finally conquer cancer
-- once and for all? Will we ever bridge the ideological and political
divides in the stem cell debate? Does the rush to develop anti-aging
drugs mean we are on the verge of finding the fountain of youth? As we
genetically eliminate disease and pick and choose the attributes of our
children, will knowing the code of life change what it means to be human?
This groundbreaking work also discusses the rapidly
expanding use of DNA technology to solve crimes, the business of genomics,
and the implications for the economy and the investment community.
As society grapples with the enormous challenge of a truly new frontier,
we must all educate ourselves about the "what," even as we seek to answer the infinitely larger question
of "why." The Genomics Age is the perfect place
to begin.
"A superb general-audience exposition
of a complex subject that is already transforming our lives and will
do so even more dramatically in the near future. Gina Smith demonstrates
that her established skills at writing and at communicating science
are just as impressive in combination as we already knew they were
separately." -- Aubrey de Grey, biogerontologist,
University of Cambridge, England
" A reader with no background knowledge of genetics will find The Genomic Age
a welcome primer -- providing disarmingly easy access to a complex array of issues
in the unfolding saga of the human genetics revolution." -- Troy Duster, author of Backdoor to Eugenics
Excerpt
Therapeutic Cloning
and Stem Cell Research
An Excerpt from THE GENOMICS AGE
by Gina Smith
INTRODUCTION
The excerpt, below, is a brief, plain-English guide
to stem cell research. It includes news of a breakthrough in non- reproductive
parthenogenic cloning that may provide a socially-acceptable alternative
to current harvesting techniques. Stem cell research is being used in
the treatment of Parkinson's disease, muscular dystrophy, diabetes, Alzheimer's
disease, osteoporosis, and other degenerative diseases.
Smith is a science writer and former ABC News technology correspondent. For THE
GENOMICS AGE she conducted exclusive interviews with 23 of the
leading authorities in the field, such as James D. Watson, Francis Collins, and
Cynthia Kenyon. Somehow, she pares their observations to the minimum while covering
the major issues of controversy: controlling cancer, retarding aging, diagnosing "defects," cloning
humans, DNAfingerprinting, DNA discrimination, and genetically-enhanced babies.
More information about the book, THE GENOMICS AGE,
and author Gina Smith follows the excerpt. Thank you for considering this material.
Therapeutic Cloning
and Stem Cell Research
by Gina Smith
Therapeutic cloning involves the replication
of human embryos to harvest stem cells for medical uses. Most clones
are created through a process called "somatic cell nuclear transfer." Essentially, a scientist
uses a tiny needle to pull DNA material from the nucleus of a donor cell
and transfer it into a hollow egg. The egg has had its own nucleus and
genetic material removed. To get this hybrid cell to start dividing,
lab technicians then "stimulate" the egg with a chemical bath
or a jolt of electricity.
Instead of implanting the resulting embryo into a female host, as would be
done in reproductive cloning, scientists destroy the embryo so that researchers
can extract the stem cells. Stem cells are pluripotent; they have the potential
to form any cell or tissue in the human body. They are master cells, capable
of morphing into cells in the brain, muscles, or other organs, and which might
be used for medical treatment.
In 2001, Great Britain became the first country in the world to legalize the
creation of human embryos -- not to create living human clones, but to create
embryos whose stem cells can be taken for experimental use. Under new regulations,
these clones must be destroyed after 14 days, and it is illegal to create live
babies by cloning.
Many scientists who urge a ban on reproductive cloning urge that the ban not
be extended to therapeutic cloning and the harvesting of stem cells to cure
disease. Scientists say the use of stem cells to grow new cells has the potential
to treat or cure dozens of degenerative diseases, from heart disease to Parkinson's
to kidney failure.
"I am convinced that therapeutic cloning offers health opportunities that
you could not attain in any other way," says Ian Wilmut, adding that it
shouldn't be banned along with reproductive cloning (NewScientist.com, November
7, 2003). Wilmut is the scientist who cloned Dolly, the sheep, in 1996 and is
now a leading commentator on the subject of cloning.
Responding to fears that if therapeutic cloning is allowed, some renegade
researcher may decide to implant a cloned embryo, rather than destroy
it, Wilmut says, "We
can't stop this valuable research from going forward for fear of a few bad
apples out there. That's why there are laws."
Stem Cell Treatments for Parkinson's Disease
Could stem cell technology help reverse the physical decline suffered by Parkinson's
patients?
Many scientists say yes. Renowned stem cell expert, Swedish researcher Olle
Lindvall, in an article at NewScientist.com (November 7, 2003), says he expects
to be able to transform stem cells into the dopamine-producing neurons Parkinson's
patients so badly need. But it will take time.
"Stem cells could potentially be used for the treatment of Parkinson's disease
-- but it's a very difficult problem to generate large numbers of dopamine-producing
neurons, which are the cells we need," Lindvall says. "I am convinced
that stem cell technology can become in the future a cure for conditions leading
to brain injury -- but I think we have a long way to go."
Scientists have had some success treating Parkinson's in animals using stem
cells from aborted animal fetuses, Lindvall says, but those stem cells aren't
as effective as the ones harvested from very early embryos of just a few days
old.
And there is another possibility. Linvall's research has shown that the brain
of a rat, after a stroke, actually produces new brain cells that travel to
the damaged area. Perhaps that process -- plus some encouragement from drugs
and combined with stem cells treatments - may be the eventual treatment for
Parkinson's.
Cloning for Stem Cells
"Our intent is to use this technology to generate stem cells to treat serious
and life-threatening diseases, not to create a child," says Robert Lanza
of Advanced Cell Technology (ACT) in an article in "Scientific American" (January
2002). He told me that his is one of the very few efforts in the world that has
successfully cloned a human embryo. ACT is one of the very few private companies
in the United States that kept working on stem cell research after the U.S. government
dried up federal funds for the procedure.
Think of an embryonic stem cell as a kind of master cell, an early-stage cell
that retains the ability to form almost any kind of cell or tissue type in
the human body. With a little chemical encouragement, a stem cell can turn
into a new heart muscle for a heart attack victim; new neurons for stroke,
paralysis or Parkinson's patients; or new insulin-secreting pancreas cells
for diabetics. Down the road, scientists believe it will be possible to create
such complicated structures as blood vessels, liver tissue, and whole kidneys.
In fact, ACT scientists have already succeeded in building tiny cow kidneys
that could be used for kidney transplants. It isn't hard to envision, Lanza
says, a future where pretty much any kind of organ or tissue could be engineered
to replace those damaged by age, injury, or disease.
"It's not science fiction at all. This field is moving ahead so phenomenally
quickly that by the time the baby boomers age, this could be routine stuff," says
Lanza, in an interview with the author (December 15, 2003). Lanza adds that scientists
have already developed techniques that could cure macular degeneration, a malfunction
of the retina that leads to poor vision and blindness in more than 1.7 million
Americans. But getting such techniques into the clinical trial stage is quite
another matter. "We only have eight scientists and thanks [to the federal
funding ban], there are times when we can barely make payroll. "My hope
is that as soon as we can show that we can cure diabetes in dogs, people will
clamor for this. And then," Lanza says, "everything will change."
Researchers Create Joint From Stem Cells
Scientists say they've managed to build the ball-structure of a joint from
adult stem cells retrieved from a rat's bone marrow.
Working at the University of Illinois in Chicago (UIC), researcher
Jeremy Mao says he succeeded in transforming stem cells into the bone
and cartilage tissue of a human jaw joint. "This represents the first time a human-shaped [jaw
joint] with both cartilage and bone-like tissues was grown from a single population
of adult stem cells." Mao, who is director of the University's tissue
engineering laboratory and a professor of bioengineering and orthodontics,
was speaking at a UIC press conference on December 1, 2003.
"Our ultimate goal," adds Mao, "is to create a [jaw joint] that
is biologically viable -- a living tissue construct that integrates with existing
bone and functions like the natural joint." So far tested only in animals,
the procedure promises to lead to technology that may help doctors replace hip,
knee, and shoulder joints that are damaged by arthritis or other disorders.
The procedure is relatively straightforward. First, researchers prodded the
stem cells, with appropriate chemicals, nutrients, and growth hormones, to
turn into cells capable of producing cartilage and bone. Then they separated
the cells into two layers and poured them into a mold created by the jaw bone
of a human cadaver. After a few days, researchers were delighted to discover
that they had what they were looking at -- joint-shaped tissue that had bone
on the inside and cartilage on the outside, just like a human joint.
Tests confirmed that the engineered tissue actually was bone and cartilage,
with all the typical components they have, including calcium and cartilage.
Generally, adult stem cells - that is, stem cells found in bone cartilage -
aren't as versatile as stem cells harvested from embryonic tissue. But this
study suggests adult stem cells may be more useful than previously thought.
Stem Cells May Treat Muscular Dystrophy
Studies in mice show that a type of stem cell in blood vessels could help patients
suffering from the muscle-wasting disease, muscular dystrophy (MD).
Researchers in Milan and Rome have discovered that blood vessel stem cells
actually cross from the bloodstream into muscular tissue, where they help generate
new muscle fibers. It worked in mice with symptoms similar to those generated
by MD, researchers say.
"Although these results are exciting, we have not cured the mice," said
Giulio Cossu of the Stem Cell Institute of Milan, speaking at a press conference
at the American Association for the Advancement of Science on July 10, 2003. "We
believe this is a significant step toward therapy, but the question that keeps
me awake at night is whether this will work in larger animals."
This particular kind of stem cell is new to scientists, having only been discovered
a year ago. According to Cossu, they are still learning how to identify them
by appearance and function, and they've so far only isolated them from fetal
blood cells. Moreover, researchers need to refine the part of the procedure
that involves inserting a healthy version of the gene that causes MD into the
stem cell. Only more experimentation will show whether the procedure will ever
be safe enough for humans.
As far as Cossu's mice go, they definitely improved as a result of the procedure.
After treatment, their muscles were larger and had more muscle fibers. They
were also able to walk on a wheel for a longer period of time than untreated
animals. "I'm convinced this is an important result, but this is still
not the therapy - for mice or for patients," Cossu told the press, underlining
that the technique is still very much experimental.
The Debate
In the meantime, the debate rages on. President George W. Bush has
made no secret of where he stands on the issue of stem cell research.
In a televised address to the nation in August, 2001, he said, "We
recoil at the idea of growing human beings for spare body parts, or
creating life for our convenience."
And the United Nations (U.N.), which was prepared to enter into a long-tem
treaty to stop scientists from pursuing human reproductive cloning, instead
hit a deadlock when the United States, the Vatican, and fifty Catholic countries
pressured the U.N. to ban therapeutic cloning, too. The whole issue is now
shelved until delegations have put more study into it. The treaty wont come
up for discussion again until 2005.
The reaction among scientists varied widely. Some, like Bob Ward, spokesperson
for the Royal Society in the U.K., said, "No decision is better than the
wrong decision."
In other news reports, some scientists say they felt cheated. "Rather
than ban the thing we all agree on, we end up with no ban, because the extremists
refuse to compromise," says Larry Goldstein, a stem cell researcher at
the University of California at San Diego (NewScientist.com, November 7, 2003)
Some observers are concerned that the U.N.'s delay in banning human reproductive
cloning gives scientists hoping to make a big name for themselves or a fast
buck from creating human clones some sort of safe haven.
Parthenogenesis: An Easy Answer?
In January 2004, Lanza and his fellow scientists at ACT made an announcement:
They had succeeded in bringing a human embryo to the point of 100 cells through
a technique called parthenogenesis. This was important news.
The same kind of reproduction
that occurs in snakes and
some birds, parthenogenesis
leads to the creation of embryos (or "parthenotes") that don't include
the male chromosomes required to make a placenta, so they could never be born
as a living human. Perhaps stem cells created through this method won't be
as controversial, and it could become the primary way stem cells are harvested
for therapeutic purposes.
"This is an ongoing research project and there are many steps ahead, including
developing the cells into viable therapies," says Lanza.
The whole issue of a looming United States and, possibly, United Nations ban
on cloning riles Lanza, who claims that stem cell therapy is the best shot
that millions of Americans have to adequately treat their degenerative disorders.
"It's unconscionable," says Lanza, "for
Catholics and other evangelists to deny others the right to receive
medical therapies. It's the whole issue of church and state. Who is
the government to be taking sides in these religious debates? They
should be looking out for the health and well being of their citizens."
At this writing, the U.S. House of Representatives had passed a bill that bans
all forms of cloning. The same measure was stalled in the Senate. In the meantime,
Lanza pursues his work while it is still legal -- and waits.
GINA SMITH is one of the best-known
science and technology journalists in America today. As the former technology
correspondent for ABC News, she has reported on stories for World News
Tonight with Peter Jennings, Nightline with Ted Koppel, 20/20, Good Morning
America, and This Week with Sam Donaldson. Her award-winning column, "Inside
Silicon Valley," chronicled the world of tech for the San Francisco
Chronicle and Examiner for a dozen years. Her sci-tech columns and stories
have also appeared in such diverse publications as The Los Angeles Times,
Wired, Popular Science, Upside, Glamour, and The Hollywood Reporter.
Her weekly radio show, On Computer with Gina Smith, has reached millions
of households in the United States and overseas, via the Armed Forces
Radio Network.
Smith's far-reaching work translating science topics in plain-English has earned
her a number of awards, including a first place in investigative journalism from
the Computer Press Association. She has been included in Upside's "Technology
Elite 100" and in the San Jose Mercury News' "Top Movers and Shakers
in Silicon Valley." An in-demand public speaker at technology forums, conferences,
and conventions, she currently serves on the Board of Councilors at the University
of Southern California School of Engineering.
