- Email: [email protected]
Molecular genetics
Current Obstetrics & Gynaecology (2000) 10, 119 © 2000 Harcourt Publishers. Ltd doi:10.1054/cuog.2000.0134, available online at http://www.idealibrary.com on
Editorial
Molecular genetics
The human genome, cloning research—genetics is constantly in the news. How does current genetic research relate to our practice of obstetrics and gynaecology? In this issue our articles explore the importance of genetic research and screening and diagnosis. As an acceptance of these techniques becomes more widespread and the procedures themselves more common, attention is inevitably drawn to the risk/benefit ratio. It is no longer a matter of the attraction of the application of new technology, applying new techniques just because we can do them, but now a matter of potential clinical usefulness. Chorionic Villous Sampling (CVS) has been around for some years and the inherent dangers to the pregnancy are well understood. Non-invasive fetal cell isolation, isolating fetal cells from maternal blood, would allow early diagnosis of fetal genetic anomaly without risk to the mother or to the pregnancy. Progress has been relatively slow in this area because of the difficulty of isolating a few fetal cells from the large number of maternal cells in the circulation and the problem of developing a technology that is near 100% accurate before it can be put into clinical practice. Alec McEwan and Lindy Durrant describe the current situation in their article. Although in their infancy, these techniques do show great promise. On the other hand, techniques that appear much more complex and inherently more dangerous are actually becoming successful. Alan Handyside brings us up to date on preimplantation genetic diagnosis, showing that there is the potential for successful outcomes as great as with conventional prenatal diagnosis, without the handicap of therapeutic termination of pregnancy later in the first or second trimester.
Our knowledge of the genetics of cancers improves all of the time. The identification and screening of high risk populations for a variety of cancers around the body is now becoming possible. How applicable is this to gynaecological cancers? As Jackie Cook shows, probably more applicable than most of us realise. On the one hand, a careful family history from patients presenting with gynaecological cancers is clearly mandatory in order to identify those families in which help can be given to other female members. The obverse of this is the more common problem presenting to gynaecological oncologists today, the increasing number of young women presenting requesting screening for gynaecological cancers because of older relatives being affected. A clear understanding of the criteria that need to be applied to identify families that can be helped is of great importance. It will be a minority of cases that require further investigation and who may ultimately be helped and it is vital to understand how these families are identified in order to avoid the considerable waste of resources inherent in screening large numbers of women who are at very low risk. Finally, genetic techniques are being used to understand basic pathology. Inherited spermatogenic failure in male infertility may seem an unlikely entity, but these conditions have the potential to increase as assisted conception techniques improve and overcome the problem, allowing further inheritance. The development of appropriate therapy depends upon the understanding of pathology. Whilst linkage analysis and the biochemistry of genetics may remain the province of the clinical geneticist and molecular biologist respectively, it is incumbent upon obstetricians and gynaecologists to understand what can and cannot be done in translating this work to clinical practice for the benefit of their patients.
Professor I. R. Johnson, School of Human Development, Academic Division of Obstetrics & Gynaecology, Queen’s Medical Centre, Nottingham, UK
119
Editorial
Molecular genetics
The human genome, cloning research—genetics is constantly in the news. How does current genetic research relate to our practice of obstetrics and gynaecology? In this issue our articles explore the importance of genetic research and screening and diagnosis. As an acceptance of these techniques becomes more widespread and the procedures themselves more common, attention is inevitably drawn to the risk/benefit ratio. It is no longer a matter of the attraction of the application of new technology, applying new techniques just because we can do them, but now a matter of potential clinical usefulness. Chorionic Villous Sampling (CVS) has been around for some years and the inherent dangers to the pregnancy are well understood. Non-invasive fetal cell isolation, isolating fetal cells from maternal blood, would allow early diagnosis of fetal genetic anomaly without risk to the mother or to the pregnancy. Progress has been relatively slow in this area because of the difficulty of isolating a few fetal cells from the large number of maternal cells in the circulation and the problem of developing a technology that is near 100% accurate before it can be put into clinical practice. Alec McEwan and Lindy Durrant describe the current situation in their article. Although in their infancy, these techniques do show great promise. On the other hand, techniques that appear much more complex and inherently more dangerous are actually becoming successful. Alan Handyside brings us up to date on preimplantation genetic diagnosis, showing that there is the potential for successful outcomes as great as with conventional prenatal diagnosis, without the handicap of therapeutic termination of pregnancy later in the first or second trimester.
Our knowledge of the genetics of cancers improves all of the time. The identification and screening of high risk populations for a variety of cancers around the body is now becoming possible. How applicable is this to gynaecological cancers? As Jackie Cook shows, probably more applicable than most of us realise. On the one hand, a careful family history from patients presenting with gynaecological cancers is clearly mandatory in order to identify those families in which help can be given to other female members. The obverse of this is the more common problem presenting to gynaecological oncologists today, the increasing number of young women presenting requesting screening for gynaecological cancers because of older relatives being affected. A clear understanding of the criteria that need to be applied to identify families that can be helped is of great importance. It will be a minority of cases that require further investigation and who may ultimately be helped and it is vital to understand how these families are identified in order to avoid the considerable waste of resources inherent in screening large numbers of women who are at very low risk. Finally, genetic techniques are being used to understand basic pathology. Inherited spermatogenic failure in male infertility may seem an unlikely entity, but these conditions have the potential to increase as assisted conception techniques improve and overcome the problem, allowing further inheritance. The development of appropriate therapy depends upon the understanding of pathology. Whilst linkage analysis and the biochemistry of genetics may remain the province of the clinical geneticist and molecular biologist respectively, it is incumbent upon obstetricians and gynaecologists to understand what can and cannot be done in translating this work to clinical practice for the benefit of their patients.
Professor I. R. Johnson, School of Human Development, Academic Division of Obstetrics & Gynaecology, Queen’s Medical Centre, Nottingham, UK
119