Expecting parents often get asked whether they want a boy
or a girl. Idle small talk? Perhaps, but today this
once-wishful reply can be made real due to the existence of
a medical procedure known as preimplantation genetic
diagnosis.
First performed in 1989, the complex and still rare
procedure is intended to weed out genetically defective
embryos before they have a chance to develop. It is usually
requested by prospective parents who are concerned about
passing an incurable genetically based disease or disorder,
like cystic fibrosis or Huntington's disease, to their
child. Typically, one or both partners have been
genetically screened and found to be a carrier.
Presently, cells from an embryo can be checked for dozens
of genetically determined diseases. PGD can also be used to
select the sex or other genetic characteristics of
embryos.
Predictably, the procedure has fostered much debate. Is the
power to identify and select the genetic characteristics of
their children one parents should have? And, if so, should
the government impose strict limits on the procedure's
use?
These and similar questions will be fielded at an upcoming
forum titled "Custom Kids? Genetic Testing of Embryos,"
hosted by the Johns Hopkins University
Genetics and Public
Policy Center. The event will convene a diverse panel
of leaders to discuss the ethical, social and scientific
implications of this potent new technology. It will take
place from 9 to 11 a.m. on Thursday, Jan. 8, at the
Renaissance Hotel in downtown Washington, D.C.
The panel will include Newt Gingrich, former speaker of the
House; Laurie Goldberg Strongin, whose son had a genetic
disease; Amy Laura Hall, assistant professor of theological
ethics at Duke University; Bernadine Healy, former
president and CEO of the American Red Cross and former NIH
director; Paul Miller, commissioner of the Equal Employment
Opportunities Commission; Tom Murray, president of the
Hastings Center, a bioethics research institute; John
Podesta, president of the Center for American Progress and
chief of staff to President Clinton; and Joe Leigh Simpson,
chair of the Department of Obstetrics and Gynecology and
professor of genetics at Baylor College of Medicine.
The event will begin with a short introduction on what PGD
is, followed by a presentation on current policy governing
the procedure and then a panel discussion.
Kathy Hudson, founding director of the Genetics and Public
Policy Center, said that the primary intention of the forum
is to stimulate a public conversation on the current and
future use of preimplantation genetic diagnosis.
"PGD grew up in a relatively unregulated environment, and
many feel it's in need of some reform and oversight," said
Hudson, who is also a professor at the School of Medicine's
McKusick-Nathans Institute of Genetic
Medicine. "Some are asking, Should this procedure be
allowed at all? Others want to know if there should be
limitations placed on its use, such as only in the case of
a couple at risk of having a child with a severe genetic
disease."
The PGD procedure begins with a woman being given a drug to
induce "super ovulation," resulting in the creation of many
eggs that are then harvested. Next comes in vitro
fertilization, where the eggs are placed in a dish and
fertilized by sperm, typically from the woman's partner.
After three days, the embryos have reached a stage when one
or two cells can be removed and subjected to molecular
analysis that helps identify specific DNA or chromosome
anomalies. Embryos that are found free of abnormalities are
then implanted in the woman's womb. The others are usually
frozen or destroyed. If the procedure does not produce a
pregnancy, it can be repeated.
To date, roughly 1,000 babies have been born following PGD,
which costs in the range of $12,000 to $16,000.
Garry Cutting, a professor at the Institute of Genetic
Medicine and director of the DNA Diagnostic Laboratory at
The Johns Hopkins Hospital, said that the technology is
still in its infancy and less than a dozen labs worldwide
offer the procedure. However, he said Johns Hopkins is
preparing to do a PGD program, and he expects the screening
to become much more widespread in the next five to 10
years.
"This technology offers parents a considerable, terrific
option," Cutting said. "Through the use of preimplantation
genetic diagnosis, they can have a much higher degree of
confidence that once the pregnancy ensues, the child will
not be inflicted with the genetic disease that one or both
of the parents is a carrier for."
Cutting said that while prenatal testing offers some of the
same benefits, one inevitable outcome of that procedure may
be the termination of the pregnancy, which carries with it
emotional, physical and financial costs.
Cutting said that this week's forum can and should be a
springboard for public debate on the PGD topic.
"I expect the talk to focus on what kinds of things we
should consider testing for," he said. "One could certainly
envision the government regulating what laboratories could
offer. Perhaps the public will ultimately decide that
offering preimplantation genetic diagnosis for the
determination of sex, for example, is OK. We need to first
ask these questions and discuss what the ethical and
political ramifications are for the use of this
technology."
The Genetics and Public Policy Center was established in
April 2002 to be an independent and objective source of
information on genetic technologies and genetic policies
for the public, media and policy-makers. The center, funded
by the Pew Charitable Trusts, is a part of the Phoebe R.
Berman Bioethics Institute at Johns Hopkins.
Hudson said that the Jan. 8 event fits in perfectly with
the center's mission in that its purpose is to inform and
offer a holistic look at an issue.
"This event, I feel, will help begin to stimulate public
conversation on this technology and future policy
directions," she said. "The center does not make
recommendations. Rather, we propose a set of alternatives
and a detailed accounting of the pros, cons and
consequences for each of those alternatives. Reproductive
policy in general tends to be a very polarizing debate. We
are hoping the information that comes out of this event
will get us outside the extreme corners of the issue and
toward some middle ground."
To register for the event or to learn more about the
Genetics and Public Policy Center, go to
http://www.dnapolicy.org.