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Genetic engineering

Judaism and genetic engineering

Jewish experts have thought particularly hard about genetic engineering. This is partly because their community has an obvious application for the technology since there's a particular genetic disease, Tay Sachs, that targets some types of Jewish people, and partly because Jewish law, Halacha, has examined medical issues in great depth throughout history.

It's also a painful subject for the Jewish community, not just because of the suffering of individuals, but because false genetic and eugenic arguments were used to justify the Holocaust in which over 6 million Jews were murdered.

Problems and questions

• Is it right to screen for an incurable genetic disease that doesn't show itself till middle-age, like Huntingdon's disease?
• Screening will prevent the disease being passed on, but it will also destroy the life of the person who hasn't yet shown symptoms of the disease, by filling even their pre-symptomatic period with fear.
• What about someone found to be a Tay Sachs carrier:
  • Where do they stand when considering marriage?
  • Should they disclose their carrier status to a possible partner - and at what stage in the relationship?
  • Should they ask about the carrier status of a prospective partner - and at what stage in the relationship?
• What about a couple who discover that they're both carriers:
  • Should they cancel the wedding?
  • Should they have a childless marriage?
• Should mass population screening be carried out for such diseases?

Tay Sachs disease

Tay Sachs disease is a fatal genetic disorder in children that causes progressive destruction of the central nervous system.

This disease is controlled by a pair of genes on chromosome 15. If both genes are inactive the person has the disease and dies very young. If one gene is active the person is perfectly healthy - but they are a carrier of the disease.

If they marry another person who is a carrier there is 25% chance that any child they have will have the disease and a 50% chance that any child they have will be a carrier.

Jewish people with an Ashkenazi background are much more likely to be Tay Sachs carriers than the rest of the population.

Premarital screening

This has been widely done to find people carrying the gene for Tay Sachs disease. In the USA over 70,000 people have been screened for the Tay Sachs gene, and over 100 couples have been discouraged from getting married as a result.

In Israel, screening for carriers has cut the number of Tay Sachs children born to newlywed ultra-orthodox Ashkenazi Jews to zero.

Some Jewish authorities are unsure whether it's right for a couple who are both carriers to marry and not have children. They say that there is a obligation in a marriage ('be fruitful and multiply') to have children and that the possibility of having an abnormal child does not remove this obligation.

Prenatal screening

Prenatal screening

It's possible to carry out tests to show whether an embryo in the womb has Tay Sachs disease, but this raises the ethical issue of whether to perform an abortion if the result is positive.

Some rabbis would say that the fact that an embryo will become an abnormal child is not a sufficient reason for aborting it and that it is in fact unethical to perform the test at all because performing this (pointless) test risks the health of the embryo.

Other rabbis say that Tay Sachs disease is a sufficient reason for aborting the foetus in the first three months of the pregnancy; others say that the physical and mental pain that having such a child would cause the parents is so great that abortion is acceptable to a very late stage of the pregnancy.

Preimplantation screening

There's a high-tech way for a couple who are both carriers to avoid the ethical problems of prenatal screening.

This is to use in-vitro fertilisation and to screen the fertilised eggs for Tay Sachs disease. Only healthy eggs would be implanted and the others would be destroyed.

Jewish law does not regard a fertilised egg as a person before it is implanted in the womb, so the destruction of the unhealthy eggs is not abortion.

Nor is there any Jewish objection to couples using artificial conception to have a family - for example if they can't have a child in any other way.

The specific ethical issues of using artificial conception in order to screen for genetic diseases have not yet been much addressed by experts.

Preimplantation screening is a major and costly project that could cost thousands of pounds.

Genetic manipulation

Suppose that genetic surgery could correct the genes in a fertilised egg (or in the sperm and/or egg before fertilisation) so that the child would not have Tay Sachs disease. What are the ethical problems in this case?

Fred Rosner MD, an authority on the subject, thinks that there should not be a problem:

• It could be regarded as carrying out the duty of physicians to heal the sick
• Processes invisible to the human eye are not forbidden in Jewish law
• The egg, fertilised egg, or sperm is not a person because it's not yet been implanted, so it doesn't have the ethical status of a person
• Surgery to cure a disease is ethical when carried out on a person, so it would certainly be ethical to carry it out before the egg or sperm became a person

Dr Rosner points out: it could be said that genetic engineering is unethical because it shows a lack of faith in God by altering part of God's creation. However, he finds a number of rabbis who believe that since the purpose is to heal, to do so is to obey the duty God has imposed on doctors.

This only allows genetic manipulation to heal the sick; it doesn't permit genetic manipulation to select eye-colour or other features.

General issues

There are some Jewish ethical principles that argue in favour of taking some sort of action in the Tay Sachs and similar cases:

• Jews regard humanity as being allowed (and indeed obliged) to work to make the world a better place
• Eliminating an incurable and cruel disease appears to make the world a better place without any counterbalancing ill-effects