Human genetics = génétique humaine : proceedings of the fourth International Congress of Human Genetics/comptes rendus du quatrième Congrès international de génétique humaine, Paris, 6-11 September 1971 / editors/rédacteurs, J. de Grouchy, F.J.G. Ebling and I. W. Henderson.

  • International Congress of Human Genetics 1971 : Paris, France)
Date:
1972
Catalogue details

Licence: Attribution-NonCommercial 4.0 International (CC BY-NC 4.0)

Credit: Human genetics = génétique humaine : proceedings of the fourth International Congress of Human Genetics/comptes rendus du quatrième Congrès international de génétique humaine, Paris, 6-11 September 1971 / editors/rédacteurs, J. de Grouchy, F.J.G. Ebling and I. W. Henderson. Source: Wellcome Collection.

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    8 C.O.CARTER the common congenital malformations such as spina bifida and cleft lip, the major psychoses such as schizophrenia, idiopathic epilepsy, non-specific severe mental retardation and many others. Here again precise diagnosis is important; for example cleft lip with mucus pits of the lower lip is a dominant condition. It is important to remember also that an empirical risk estimate established for one particular population will not necessarily apply to another, particularly if the condition in the other population has a markedly diff'erent birth frequency. RISKS IN PERSPECTIVE Two considerations in putting estimates of risks into perspective are first to relate the additional risk in a particular pregnancy to the overall risk of malformation in any random pregnancy, and secondly to explain the prognosis for the child if it should be affected. It is well known to the medical profession, but not to the layman, that in any pregnancy there is a 2 to 3 % risk of serious malformation of some kind or another. Any special risk is additional, but must be seen in this perspective. The prognosis for the child if afi'ected is important. The follow-up that colleagues and I carried out, published last year (Carter et al., 1971), showed that parents were sometimes prepared to take a high risk if the child if afi'ected would be stillborn or die in infancy. In no case did they plan a further pregnancy where the child if affected would be expected to survive for years with a major handicap. It is also necessary to explain to a parent, who for example suffers from a relatively mild manifestation of a domi¬ nant condition, that her child if affected is likely to be much more severely handicapped. A further aspect of putting risks into perspective involves a matter of principle about which there will be diff'erent opinions between one doctor and another. This is the degree to which the doctor providing information on genetic risks should also directly advise parents on whether to plan further children or not. In the future we are going to rely on genetic coun¬ selling to control the birth frequency of much genetically determined disease, but we will achieve little unless parents take responsible decisions on the basis of the information given them. In the United Kingdom, with the prevailing concept of the right and duty of indi¬ viduals to make their own decisions, and more specifically in matters medical the trend to involve the patient in all decisions, our feeling is that the ultimate choice must rest with the parents. Therefore the question I have sometimes been asked, 'Do parents take your advice?' is inappropriate. We give information and not advice. Many patients, however, do find it helpful if the doctor does also indicate the decision he would make if faced with their par¬ ticular problem. In other countries, with a more authoritarian tradition of the doctor-patient relationship, medical practitioners may well feel that they should more directly advise or instruct parents on what decisions to take. One experienced paediatrician has said that he feels he should appear to take decisions for the parents after first sensing what they them¬ selves would like to do, so that if things go wrong they can blame him and not themselves. In practice, however, parents do take sensible and responsible decisions, provided that they are given the correct information and it is put into proper perspective. PROSPECTS Coming now to future prospects for counselling and the control of the birth frequency of genetically determined disease, the major new development in recent years has been the very welcome advent, as a practical possibility, of the diagnosis at the 14th to 16th week of preg¬ nancy of a number of genetic abnormalities. This will be a great boon to those parents with a high risk of a serious condition who much want further children, but are not prepared to take the risk unless they can be offered prenatal diagnosis and a termination if the foetus should prove to be affected. Dr. Littlefield will be discussing this in more detail.