human embryos produced via cloning.23 ACT used two techniques, SCNT and parthenogenesis, to produce human embryos. ACT researchers obtained eggs from seven women, ages 24 to 32, who were paid $3,000 to $5,000. In the SCNT approach, scientists removed the nucleus from 19 eggs and replaced it with a nucleus from another adult cell. The nucleus of a skin cell was used for 11 eggs, and for the remaining eight eggs, cumulus cells were used. Eggs that received a skin cell nucleus did not divide; seven of the eggs with the cumulus cell nucleus began to divide but division stopped at the four-to-six-cell stage. In parthenogenesis, an egg cell is treated with chemicals causing it to divide without being fertilized by a sperm. ACT exposed 22 human eggs to the chemicals. After five days, six eggs had matured into a larger mass of cells before division stopped. None of the embryos developed by ACT divided sufficiently to produce stem cells. ACT suspended its work in 2004.
The goal of ACT’s work was to produce human embryonic stem cells and develop new therapies for diseases such as diabetes and Parkinson’s disease.24 Scientists believe that stem cells transplanted into a patient could treat disease or injury by replacing damaged tissue. If the cell nucleus used in SCNT is from the patient, the stem cells would be genetically identical to the patient, recognized by the patient’s immune system, and would avoid any tissue rejection problems that could occur in other stem cell therapeutic approaches. Because of this, many scientists believe the SCNT technique may provide the best hope of eventuallytreating patients using stem cells for tissue transplantation.
Others with Human Cloning Intentions. Within a year of the Dolly announcement, concerns over human cloning were heightened when Dr. Richard Seed, a Chicago scientist, announced on January 7, 1998, his intention to clone a human being. In response, bills were introduced in the 105th Congress that would have banned human cloning indefinitely or imposed a moratorium. The legislation was opposed by a number of medical organizations, the biotechnology industry and many scientists and was not enacted.
Others who have expressed an interest in reproductive cloning include Dr. Panos Zavos, of the University of Kentucky, and Dr. Severino Antinori, director of a fertility clinic in Rome. At one time, Dr. Zavos and Dr. Antinori were working together to help infertile couples have children via cloning. In April 2002, there were unconfirmed reports in the media that Dr. Antinori had implanted cloned human embryos in women. Dr. Antinori claimed there were three such pregnancies of six- to nine-weeks’ duration, two in Russia and one in an Islamic state. His claim was disputed by his former partner Dr. Zavos. In January 2004 Dr. Zavos announced that he had implanted a cloned embryo into a woman’s uterus; two weeks later he stated that the pregnancy had failed.25
23 J. B. Cibelli, et al., “Somatic Cell Nuclear Transfer in Humans: Pronuclear and Early Embryonic Development,” Journal of Regenerative Medicine, vol. 2, Nov. 26, 2001, pp. 25-31.
24 For more information about stem cells, see CRS Report RL31015, Stem Cell Research, by Judith A. Johnson and Erin Williams.
25 David Derbyshire and Oliver Poole, “I Am Doing God’s Work, Insists Maverick Fertility Expert Who Wants to Clone Babies,” Daily Telegraph, Feb. 14, 2004, p. 4.