How scientifically plausible are fears that in the future people will be bred using genetic engineering or cloning, or that human–non-human hybrids will be created? Speculation that these nightmarish consequences will follow from continuing human pre-embryo experimentation has been fuelled by recent advances in reproductive medicine and genetics. Some information for determining whether these claims represent scientific possibility or fantasy, together with a consideration of whether continuing human pre-embryo experimentation will contribute to their realization, is provided in the following discussion.

Using genetic engineering in human breeding

Genetic engineering involves the transfer of genetic material (DNA) determining a specific trait from one individual to another individual from the same species, or of a different species. Some of the human abilities seen as likely candidates for genetic engineering include athletic ability, strength, beauty and intelligence. What are the prospects of creating a race of specially designed people excelling in one of these characteristics using genetic engineering?

A problem confronting any plan for breeding humans is the time required before any results can be assessed. The time involved will be years, which in itself may act as a deterrent for such schemes. One way to reduce the time required to ‘tailor-make’ people through genetic engineering would be to use female embryos, derived from adult females and males scoring well for traits other than that to be genetically engineered, as a source of eggs.