Donnai and Elles provide a comprehensive description of the current organisation of regional genetic centres within the United Kingdom. Their account particularly reflects the foresight of the founders of this specialty service and the cooperative partnerships forged between universities and the NHS in the 1970s and 1980s. To deliver the health benefits of the post genome era, regional genetic centres need to respond to the rapidly accelerating pace of scientific and technical development. Whereas regionally based cytogenetic and molecular genetic laboratories have successfully implemented services for the most commonly occurring or easily tested inherited disorders, this model is unsustainable for the thousand or so genes already known to be involved in the rarer genetic diseases.
To cope with the increasing demand for a much more diverse range of genetic tests, molecular geneticists have developed an informal network for genetic testing throughout the United Kingdom. This allows samples to be cross referred between laboratories that offer different tests. The introduction of new gene tests is, however, rarely subject to critical cost-benefit analysis, and the transition from research into service is often ad hoc, being determined by local interests and enthusiasm. Support and validation for the network and new tests that might be offered is needed urgently. A recent report by an expert working group for the NHS Executive and the Human Genetics Commission has recommended that the Department of Health acts now to consolidate this network.1-1
The identification of genes involved in common diseases and responses to drug treatment raises further and even greater uncertainties for the future provision of services. Recent developments in cancer genetics provide useful insights. Several genes conferring a high risk of breast, ovarian, or colorectal cancer were identified during the 1990s. These genes seem to account for less than 5% of all cases but a higher proportion of cases with a strong family history and young age at diagnosis. Publicity surrounding these discoveries has generated unprecedented pressure on regional genetic centres, much of it from families in which the genes concerned are unlikely to be involved. Although centres are responding by establishing filtering mechanisms to identify the minority of families at high genetic risk, the concerns of those at moderate or low risk can only be effectively dealt with in partnership with primary care.
Further surges in demand for genetic information and testing in relation to common polygenic disorders are likely, although enthusiasts may be prone to overestimate this demand and the utility of genetic testing for complex polygenic diseases. By contrast, the recent genetics scenario project from the Nuffield Trust has emphasised the appreciable potential of pharmacogenomics to tailor drug choice and dosage in individual patients.1-2
In the face of these new developments there is a clear need for action. Firstly, a system throughout the United Kingdom must be consolidated for the evaluation and implementation of new genetic tests for rare genetic diseases. The planning of resources and manpower for counselling and clinical services, which are integral to genetic testing, must be included in this process. The recent formation of a Genetics Commissioning Advisory Group within the National Specialist Commissioning Advisory Group is an important development in this regard. Secondly, regional genetic centres must form partnerships with primary care and with public health to evaluate new developments in the genetics of common diseases. Thirdly, new partnerships will be required with other hospital based specialties. Pathology laboratories, for example, increasingly have the potential to identify somatic clues indicative of inherited mutant genes. For instance, detection of instability affecting repetitive DNA sequences in cancer tissue can suggest hereditary non-polyposis colorectal cancer. The increasing accessibility of DNA technology will force re-examination of the traditional divide between the analysis of somatic and germline mutations.
The experience of regional genetic centres in dealing with issues of confidentiality and the implications of genetic testing for family members will be invaluable in relation to these clinical and laboratory challenges. If resourced they are well placed to provide education and training on inherited disease for other specialties. And as Donnai and Elles suggest, the developing role of the genetic counsellor may be particularly relevant to primary care.