Overview: Genetic Issues
Advances in
genetic technology have been among the most startling and controversial
scientific developments in recent years. Genetic screening, genetic
engineering, and cloning raise essential questions about human nature and power
and are thus among the most difficult and exciting issues in bioethics.
Screening for
genetic diseases can be conducted at various points of human development.
Carrier screening can be done to determine whether a person has an unhealthy
gene that could be passed on to a child. Pre-implantation screening can be done
on a zygote that has been fertilized in vitro, which can then, in theory, be
discarded if a genetic malady is discovered. Prenatal testing can detect
diseases like Tay Sachs during pregnancy, when abortion is a logistical option.
From a Jewish
perspective, carrier screening is the most favorable of these options. Two
people who test positively for the Tay Sachs gene can be—some say should
be—discouraged from marrying. However, it is important that the results of the
screening be kept confidential to avoid genetic discrimination. Amniocentesis,
in which a small amount of the fluid surrounding a fetus is extracted from a
pregnant woman—as well as chorionic villi sampling (CVS), which can be done
even earlier in pregnancy—can determine whether a fetus carries a genetic
disease like Tay Sachs or is affected with Down syndrome (which cannot be
detected through carrier screening).
There is no
consensus about whether abortion is permissible if such testing does discover
an affected fetus. Those like the late Rabbi Moshe Feinstein who reject
abortion in such cases also question the permissibility of amniocentesis.
However, there are rabbis, such as Eliezer Waldenberg, who permit both
amniocentesis and abortion if a terminal disease like Tay Sachs is discovered.
For a non-terminal condition, the permissibility of testing and abortion are
less clear. Authorities disagree on whether to extend
the permissibility of abortion to situations in which a fetal genetic problem
is discovered that could cause psychological danger to the mother. Pre-implantation
screening, particularly when both man and woman are carriers of a genetic
disease, is less objectionable than abortion according to all authorities.
Gene therapy is
in its early stages, and for the most part, Jewish thinkers have yet to respond
to many of the specific questions it raises. Nonetheless, certain broad
guidelines characterize Jewish positions to date. In general, genetic
engineering for therapeutic purposes is condoned and encouraged by Jewish
authorities. Consequently, stem cell research—which supporters say can yield
cures for diseases such as Parkinson’s and diabetes—has been endorsed by many
rabbis. Stem cells usually come from aborted or discarded embryos, and for this
reason many in the “pro-life” camp have rejected this practice. Jewish
bioethicists, however, cite the concept of pikuach
nefesh—the Jewish value of saving
lives—coupled with the idea that an embryo less than 40 days old is
traditionally considered “like water,” as reasons for supporting stem cell
research.
Cloning for
therapeutic purposes has also been embraced by most Jewish authorities, though
cloning for reproductive purposes (a future possibility) has been rejected by
most. Some believe that cloning would create a person in a human’s image,
rather than God’s. Others are disturbed by the possible similarity to Nazi
experiments aimed at creating a master race. However, some authorities see
cloning as a potential option for couples who can’t conceive normally. Michael
Broyde, an Orthodox rabbi and professor of law at Emory University, is among
those who argue that we should consider cloning in cases where reproduction is
otherwise impossible. He believes that cloning may be a mitzvah in such circumstances.
Beyond the life
and death health issues of genetic screening and engineering, there are other
potential and actual ethical and halakhic questions as well. Is it ethical to
pre-determine the sex of one’s child through pre-implantation screening of
embryos conceived in vitro? Is a pig that’s been genetically engineered to chew
its cud kosher? Some of these questions have been answered—a pig is, for now,
still a pig, so kosher bacon isn’t on the horizon—but more fascinating and
difficult problems are sure to be raised in the coming years.