Xenotransplantation

The Genetics Forum
3rd floor, 5-11 Worship Street, London EC2A 2BH
t + 44 (0) 171-638 0606 f + 44 (0) 171- 628 0817
geneticforum@gn.apc.org

***PRESS RELEASE - NEWS*** For immediate release Friday 17 October 1997

THE GENETICS FORUM CALLS ON THE GOVERNMENT TO ANNOUNCE A MORATORIUM ON
XENOTRANSPLANTATION AND ANIMAL PATENTS

At Papworth Hospital in Cambridge, in concert with the biotechnology
company Imutran, scientists are using genetic engineering techniques to
attempt to breed pigs which have a human gene in every cell. Imutran has
filed a patent application on the process they intend to use ultimately to
place the heart from a genetically engineered pig into a human, a process
known as xenotransplantation. Multi-million pound profits lie at the end of
this particular genetic rainbow.

But just this week, yet another scientific study warns that pig viruses may
transfer into human cells. Xenotransplants increase the risk of infection,
according to Jonathan Stoye of the National Institute for Medical Research
in London. Stoye and his colleagues have identified two different classes
of endogenous proviruses from a kidney cell line of a pig. Endogenous
viruses are passed on in the germ-line as proviruses and so are very
difficult to remove when producing animals for organ transplants. These
resulting viruses may infect human cells, causing potentially pathogenic
viruses for pig organ recipients.

"Though we do not yet know which proviruses are capable of yielding
infectious virus, the number of proviruses suggests that the breeding of
virus-free pigs, if at all feasible, will represent a complex task," the
researchers argue [1].

The government's Advisory Group on the Ethics of Xenotransplantation, the
Kennedy Group, has advised that no clinical trials should take place before
more is known about cross species viral transfer. The government has said
that it will shortly announce whether clinical trials may take place.

"This scientific announcement in Nature is the evidence needed for the
government to act according to the precautionary principle, and place a
moratorium on xenotransplantation experiments", says Dr Abby Munson,
consultant for The Genetics Forum.

"There are just too many unknowns and unknowables involved." Dr. Munson
continues: "The government's own experts have recommended no clinical trials
take place until more information is collected on a range of infectious
agents which could cause disease following xenotransplantation, including
parasites, bacteria, fungi and viruses." A range of viruses found in pigs
could be of concern, including polyomarvirus, parvovirus, circovirus,
cytomegalovirus, reproductive and respiratory syndrome virus.

The government has already approved experiments between different animal
species conducted by Imutran, which attempt to make animal organs more
similar to human organs for transplant. Dr White has introduced genes for
two human complement inactivating proteins (eg anti C5-C9 and Decay
accelerating factor DAF) into pig blastocysts. The aim of this is to try
coating pig cells with human protective
protein. If successful, the hope is that this might fool the human immune
system into accepting a pig's heart.

The Genetics Forum argues that these experiments are putting animal welfare
at risk. Existing animal welfare legislation was not created to protect
transgenic animals. The Genetics Forum calls for a study on the animal
welfare implications of xenotransplantation. "What criteria are the
government using," asks The Genetics Forum, "to measure the level of
suffering, and what level of suffering is acceptable? The government's
Kennedy report, for example, recommended that primates are not used as
source animals because it would involve too much suffering, but accepts that
pigs can be used. Why?"

The Genetics Forum calls on the government to halt xenotransplantation
experiments, and place a moratorium on animal patenting until there has been
a full impact assessment on the effects of biotechnology and patenting on
animal welfare.

Notes for editors:
[1] Nature press release, 16 October 1997.
[2] If you would like to talk to Dr Abby Munson about the issues raised
here, please call her direct on 01273 675367 or call The Genetics Forum
office on 0171-638 0606.
[3] If you would like more information on the work of The Genetics Forum,
please contact Susan Casey or Portia Dadley on 0171-638 0606.

ENDS
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The Genetics Forum
3rd floor, 5-11 Worship Street, London EC2A 2BH, UK
t + 44 (0)171-638 0606 f + 44 (0)171-628 0817 e geneticforum@gn.apc.org

The Genetics Forum, an independent thinktank on genetic engineering,
publishes 'The Splice of Life' magazine six times a year (ISSN 1362-1955).
For details of this and other publications, please send an A5 sae to the
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