The Human Fertilisation and Embryology Authority was wise to approve human-animal hybrid cells for research. Plus, Craig Venter's genome and mining the moonby Philip Ball / October 27, 2007 / Leave a comment
The HFEA and hybrids
When the Human Fertilisation and Embryology Authority (HFEA) was established in 1991, no one had much inkling of the murky waters it would be required to patrol. The HFEA was envisaged primarily as a body for regulating assisted conception, and so it was given regulatory powers over human embryo research. Sixteen years later, the HFEA is having to pronounce on issues that have little bearing on fertility and conception, but rather concern research that some people say is blurring the boundaries of what it means to be human.
So far, the HFEA has remained commendably aloof from the ill-founded fears that this research attracts. Its latest permissive ruling on the creation of human-animal cells is the outcome of sober and informed consideration of a sort that still threatens to elude the British government. It belies (in Britain, at least) the belief that Enlightenment ideals are in eclipse.
Human and non-human components might be mixed in embryos in many different ways. Some research requires human genetic material to be put into animal cells—for example, to create human embryonic stem cells without reliance on the very limited supply of human eggs. There are also arguments for putting animal genes into human cells, which could offer new ways to study the early stages of human development.
Certainly, there are dangers. Eviscerating an animal cell nucleus (where most DNA is housed) to make way for a human genome does not remove all the host’s genetic material. Such transfers, which produce so-called cytoplasmic hybrid (cybrid) cells, might, if used to make stem cells for medical implantation, risk introducing animal diseases into human populations. Recent findings that genomes can be altered by “back-transfer” of genetic information from non-DNA material add to the uncertainties.
But no one is intending at this stage to use cybrids for stem-cell treatments; they are strictly a research tool. The HFEA has decided that there is no “fundamental reason” to prohibit them—recognising, it seems, that protests about human dignity and unnaturalness impose misplaced criteria. It stresses that the ruling is not a universal green light, and that licensing will be made on a case-by-case basis. The first such applications are being considered, and are likely to be approved.
The ruling says nothing about other fusions, such as embryos with mixtures of human and animal cells (true chimeras) or hybrids made by fertilisation of eggs with sperm…