Somatic
Cell Nuclear Transfer (Therapeutic Cloning)
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Related ResourcesAAMC Documents |
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Cloning is the creation of multiple
copies of a single molecule, cell, or virus. There are many different kinds of
cloning, most of which are now commonplace in science. Cloning has allowed scientists
to develop powerful new drugs and to produce insulin and useful bacteria in the
lab. It also allows researchers to track the origins of biological weapons, catch
criminals and free innocent people, and produce new plants and livestock to feed
an undernourished world population. Somatic Cell Nuclear Transfer (SCNT)
or therapeutic cloning involves removing the nucleus of an unfertilized egg cell,
replacing it with the material from the nucleus of a "somatic cell"
(a skin, heart, or nerve cell, for example), and stimulating this cell to begin
dividing. Once the cell begins dividing, stem cells can be extracted 5-6 days
later and used for research. The AAMC supports on-going research into SCNT and
has endorsed legislation that would allow such research to flourish. Reproductive
cloning, on the other hand, is intended to create human beings by cloning human
embryos. The AAMC and the National Academy of Sciences recommend a ban on all
forms of this type of cloning. Congressional ActionCongressional
interest in issues related to human cloning remains high. In the past few years,
a number of hearings have been held on the issue and several bills have been introduced
in Congress. The only legislative vote on cloning took place in the 107th
Congress. On July 31, 2001, the House of Representatives passed H.R. 2505, introduced
by Reps. Dave Weldon (R-Florida) and Bart Stupak (D-Michigan), by a vote of 265
to 162 after rejecting an alternative bill (H.R. 2608) crafted by Reps. Jim Greenwood
(R-Pennsylvania) and Peter Deutsch (D-Florida) by a vote of 178 to 249. The major
difference between the proposals was that the Weldon-Stupak bill would have banned
all human cloning (whether for reproductive or research/therapeutic purposes)
while the Greenwood-Deutsch bill would have only prohibited cloning intended to
create a human being. Supporters of the Greenwood-Deutsch bill feared that an
all-out ban on cloning research would also impede research using pluripotent human
embryonic stem cells. The AAMC endorsed an earlier version of the Greenwood-Deutsch
bill (H.R. 2172) on June 27, 2001. The Senate did not consider the bills and they
died at the end of the 107th Congress. In the 109th Congress, several bills
related to cloning have been introduced, but none has seen action. The most prominent
bills are S. 876, the Human Cloning Ban and Stem Cell Research Protection Act
of 2005, introduced by Senator Orrin Hatch (R-Utah) and H.R. 1822 introduced by
Representative Mary Bono (R-California). S. 876 currently has 12 cosponsors and
H.R. 1822 has 5 cosponsors. Neither bill is expected to see action during this
Congress. As introduced, the bills prohibit: (1) conducting or attempting
to conduct human cloning; (2) shipping the product of nuclear transplantation
in interstate or foreign commerce for the purpose of human cloning in the United
States or elsewhere; or (3) exporting to a foreign country an unfertilized blastocyst
if such country does not prohibit human cloning. The bills set forth criminal
and civil penalties for violations. The bills would further require that research
involving nuclear transplantation be conducted in accordance with applicable Federal
regulations regarding the protection of human subjects and Institutional Review
Boards. The bills would prohibit: (1) a somatic cell nucleus from being transplanted
into a human oocyte (egg) that has undergone or will undergo fertilization; (2)
an unfertilized blastocyst from being maintained after more than 14 days from
its first cell division, not counting storage times at temperatures less than
zero degrees centigrade; (3) an oocyte from being used in nuclear transplantation
research unless donated voluntarily with the donor's informed consent; (4) a human
oocyte or unfertilized blastocyst from being acquired, received, or transferred
for valuable consideration in interstate commerce; and (5) nuclear transplantation
in a laboratory in which human oocytes are subject to assisted reproductive technology
treatments or procedures. The bills set forth stringent civil penalties for violations.
Senator Sam Brownback (R-Kansas) has introduced legislation, S. 658, the
Human Cloning Prohibition Act of 2005, which would outlaw both human reproductive
and therapeutic cloning. A similar bill, H.R. 1357, introduced by Representative
Dave Weldon (R-Florida), is pending in the House. AAMC Activity
AAMC President Jordan Cohen, M.D., on January 15, 2003, wrote Senator Orrin Hatch
endorsing his Human Cloning Ban and Stem Cell Research Protection Act. Dr. Cohen
wrote, "The AAMC joins with you in strongly opposing human reproductive cloning.
To expose any person to the known risks and uncertainties involved in reproductive
cloning would be unethical and unconscionable. However, it is important to recognize,
as your bill does, the difference between reproductive cloning and the scientific
potential of therapeutic cloning and regenerative medicine. Your bill will allow
this potentially life-saving research to move forward." |
