HUMAN-ANIMAL HYBRIDS AND CHIMERAS

  9.29  The HFE Act makes clear that a human embryo cannot be placed in an animal, or vice-versa, and that human and animal gametes cannot be mixed other than in very specific circumstances. Only a human embryo, or human gametes, may be placed in a woman. These provisions reflected public disquiet about the prospect of creating hybrid embryos (for example by the fertilisation of a human egg with the sperm of another species), or "chimera" embryos (for example by fusion of the cells of a human embryo with cells from the embryo of another species). [32]

  9.30  The Government has heard no compelling evidence that there is any reason to remove the prohibition on placing human embryos in animals (or vice-versa) and we have no intention of changing this position.

  9.31  However, the Government is aware of arguments that there may be benefits in the research use of embryos created through the combination of human and animal material. At present the mixing of human and animal gametes is only allowed (under licence) for testing the fertility or normality of human sperm, and the result of the mixed gametes must be destroyed when the test is complete and definitely no later than the two cell stage. Other human-animal cell fusion products have been widely used in biosciences research for many years, for example in the development of treatments for some types of breast cancer.

  9.32  Reasons for wanting to create hybrid or chimera embryos for research could include:

—  to test the capacity of embryonic stem cells to differentiate into a range of bodily cell types, as part of research into the treatment of serious diseases; and

—  to derive human embryonic stem cells, thereby circumventing the shortage of good quality human eggs available for research.

  9.33  The Science and Technology Committee recommended[33] that new legislation should:

—  define the nature of hybrids and chimeras;

—  make their creation legal for research purposes (provided they are destroyed in line with the 14 day rule); and

—  prohibit their implantation in a woman.

  9.34  The Committee recognised that there are strongly held views both for and against this proposal, ranging from revulsion in some quarters to arguments that the creation and destruction of such creations pose fewer ethical problems than the creation and destruction of purely human embryos.

  9.35  The Government invites views on whether the law should permit the creation of human-animal hybrid or chimera embryos for research purposes only (subject to the limit of 14 days culture in vitro, after which the embryos would have to be destroyed).

33   Human Reproductive Technologies and the Law. See recommendation 9. Back