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CHAPTER 5: OUTLINE OF GENETICS SERVICES AND RELATED PREGNANCY AND NEWBORN SCREENING SERVICES IN NHSSCOTLAND
Although legislative competence in relation to human genetics is reserved to the Westminster Parliament, responsibility for healthcare delivery in Scotland is devolved to the Scottish Parliament. Thus, genetic services within the NHS in Scotland fall within the remit of the Scottish Executive and Scottish Health Ministers.
Genetics services incorporate a range of clinical, laboratory and screening services in order to provide an effective, coordinated service to patients and their families. There are four regional genetics centres in Scotland based in the four university medical school cities of Aberdeen, Dundee, Edinburgh and Glasgow. Each of these four centres delivers integrated clinical and laboratory genetics services for their region of Scotland. Each centre runs a network of outreach clinics to remote and rural areas, as well as to the islands, to ensure equity of access to the service.
Clinical Genetics Services
The delivery of clinical genetics services revolves primarily around the provision of genetics clinics, the principal activities of which include:
- Illiciting in detail and recording relevant family information and pedigree
- Clinical assessment and investigation of affected individuals and other family members as appropriate to confirm the diagnosis
- Pedigree analysis and genetic risk assessment for patients and family members
- Genetic counselling, (the process of communicating clinical and genetic risk information to individuals and to family members to allow them to make informed choices and decisions)
- Discussion of the options that are available to help individuals and their families to enable them to choose a course of action appropriate for them, these may include pre-natal diagnostic or predictive genetic tests.
Although consultant-led these services are delivered by a multi-disciplinary team which includes in addition to the consultant clinical geneticist and genetic counsellors (or associates), others involved in calculation of genetic risks for families e.g. statisticians. Each of the regional genetic centres in Scotland is staffed with the usual mix of professionals. They run regular, routine genetics advisory clinics as well as specialist clinics. Clinical geneticists have often been trained and had extensive experience in other specialties before entering genetics. These additional clinics may, therefore, be in special aspects of genetics or may be joint clinics in association with other medical specialties such as neurology, paediatrics or ophthalmology.
Genetic counsellors (who may have either a nursing or a science background) now play an important role in the delivery of clinical genetics services in a number of different ways. By contacting referred families and obtaining preliminary information (and sometimes blood specimens for testing) before the clinic visit, they enhance the efficiency of genetic clinics. Their increasing role in providing counselling for patients with less complicated problems enables clinical geneticists to concentrate on the more complex patients. In many areas they are now providing counsellor led services, and they play a pivotal role in the delivery of cancer genetics services in Scotland. In addition, they provide a valuable liaison between the specialist genetic centres and local primary care teams.
Clinical geneticists like consultants in other specialties, are extensively involved in providing expert advice as well as informal consultative advice through personal discussions with colleagues, clinical meetings, telephone advice to GPs and inpatient consultations. Unlike most other consultants, however, the provision of outreach services frequently requires them to travel from the centres to run clinics in more remote areas which can involve a considerable amount of travelling time. In addition, they play key roles in research and the development and audit of services. They are also the cornerstone for training and education in genetics in both under- and post-graduate medical education, as well as in relation to other healthcare professions.
Scotland has a coordinated cancer genetics service which is run from the four regional genetics centres. Central funding was provided to establish posts in each centre for genetic counsellors to facilitate the liaison between primary care teams and the cancer genetics clinics and to provide a resource for 'triaging' referrals, so that primary care can more effectively act as gatekeepers for the specialist secondary service. Those patients deemed to be at lower or moderate risk are effectively dealt with by the genetic counsellors in collaboration with the primary care team. For those who are at high risk and seen within the specialist cancer genetic clinic, genetic testing for breast and colon cancer genes is provided through the Molecular Genetics Consortium laboratories in Scotland and is centrally funded.
In 2001 the Department of Health established the Genetic Commissioning Advisory Group ( GenCAG) to provide a strategic overview and co-ordinate developments across the specialist genetic services in England. The Scottish NHS services, along with those in Wales and Northern Ireland are represented on GenCAG in order to co-ordinate, as far as possible, developments across the UK.
Laboratory Genetics Services
The two main components of medical genetics diagnostic laboratory services are molecular genetics laboratories and cytogenetics laboratories. In addition, there are close links with the laboratories providing screening for Down's syndrome and neural tube defects, the laboratory providing the newborn screening service in Scotland and with those providing paediatric biochemical services, who are involved in the diagnosis and management of children with inherited metabolic disorders.
Both molecular and cytogenetics laboratory services are co-located with the clinical genetics service in each of the four centres. If not physically in the same building, they are all on the same campus. In addition, there is a cytogenetics service provided for the NHS Highland Board in Inverness. The majority of the activities of the genetics laboratories are highly specialised in nature, not only in terms of the technology involved but in terms of the expert knowledge of the scientific staff in deciding, with referring clinicians, which genetic tests are appropriate and in providing expert interpretation of test results. The complexity of techniques and unfamiliarity of many clinicians with the field of genetics creates a particular need for genetics laboratory scientists to have close links not only with the clinical genetics service, but also with other clinicians who may use their service. This forms a major activity of the senior scientists within these laboratories, and is one of the reasons why co-location of the clinical and laboratory services is so important.
The four molecular genetics laboratories in Scotland have for some years worked in a formal consortium arrangement (The Scottish Molecular Genetics Consortium ( SMGC)) which is overseen by a steering group. The service is centrally commissioned and funded as a national service for Scotland. This arrangement has been highly successful and enables total equity of access for all Scottish patients to a very comprehensive list of, often rare, molecular genetic tests enabling the retention of expertise for less common (or low volume) tests whilst avoiding wasteful duplication. Funding is also available for the purchase of tests from any laboratory outside Scotland if they cannot be provided from within the SMGC. Patients are seen and counselled by their local genetics service and the DNA from their specimens for testing is sent to the nominated laboratory within the Consortium which has responsibility for providing the relevant test. The model has enabled both specialisation and rationalisation of provision for some more common tests.
Thus, there is full access for all Scottish families to any molecular genetics test that is required for the management of a family. The tests offered by the molecular genetics service use analysis of DNA to detect a range of single gene disorders, including cystic fibrosis, muscular dystrophies and Huntington's disease. An important relatively new area is the diagnosis and prediction of inherited forms of cancer and genetic testing for inherited bowel and breast cancer has been incorporated within the service available in Scotland. Molecular genetics laboratories, therefore, play an important role in providing diagnostic testing for patients with inherited disorders, pre-symptomatic testing for specific genetic disorders of adult life and pre-natal diagnosis of inherited disorders for families at risk that require this service. Increasingly molecular genetic tests are being used for patient management in other clinical specialties, e.g. clotting factors in haematology and genotype in diabetic patients with MODY (Maturity Onset Diabetes of the Young).
In the last few years, rapid molecular tests have been introduced alongside conventional cytogenetic karyotype analysis in the pregnancy screening programme for chromosomal anomalies. As QF- PCR (rather than FISH) is the methodology used for the majority of the rapid tests done in Scotland, the bulk of this work falls on the molecular genetics laboratories. The service thus also plays a significant role in the provision of the routine screening services offered to all antenatal patients in Scotland.
The four Scottish laboratories are members of, and play a full part in, the recently established UK Genetic Testing Network. Through this mechanism tests can be arranged for Scottish families in other UK laboratories and Scottish laboratory expertise is made available for patients from outside Scotland who have rare genetic disorders.
Cytogenetics laboratories analyse the number and composition of chromosomes to diagnose genetic disorders, including specific forms of mental handicap and birth defects. The results provide important information on recurrence risk, prognosis and likely complications. They also analyse chromosomes from early pregnancy samples (amniotic fluid cells or chorionic villus samples) taken because of an identified increased risk of a genetic disorder in the fetus and they are being increasingly employed in the diagnosis and management of a variety of cancers. Increasingly traditional cytogenetic techniques are being combined with molecular DNA based approaches (molecular cytogenetics). Analysis of single genes with a combined approach that can detect an increasing range of single gene disorders, using the technique of fluorescent in situ hybridisation ( FISH). Similarly, small, sub-microscopic chromosomal deletions can be detected using fluorescent DNA probes.
There are four cytogenetics laboratories within the regional genetics centres and a fifth in Inverness, which provide routine cytogenetic analyses. Like other laboratories within the UK they carry a heavy workload in relation to the diagnosis and management of a variety of cancers, as well as the service they provide to families with genetic diseases. Recently it has been agreed that the four main cytogenetics laboratories can work within the SMGC arrangements for the provision of molecular cytogenetic tests, e.g.FISH for micro-deletion diagnosis.
A formal Users Group, composed of all the clinical geneticists in Scotland meets regularly to discuss the operation of the laboratory service and to agree the prioritisation of new developments that are proposed for the molecular and molecular cytogenetic services. Therefore, when any of the research centres in Scotland feel that they have developed a test to the degree that they wish to offer this as a clinical service, the proposals they put forward are assessed by the clinical Users Group, who prioritise them in terms of the clinical utility they attach to the tests on offer. The SMGC Steering Group then decides how many of these new developments can be implemented within the funding that is available.
Pre-natal Screening
All pregnant women in Scotland are offered a coordinated programme of pregnancy screening tests, in line with the recommendations of the National Screening Committee. There are two components to the screening programme; firstly, tests for a number of communicable diseases (syphilis, rubella, HIV and hepatitis B) and secondly, tests for Down's syndrome (and other aneuploidies) and neural tube defects.
There is now in place a standardised Scotland-wide protocol for the Pregnancy Screening Programme which standardises patient information, the tests offered, the consent procedures used and programme standards for Quality Assurance ( QA) purposes.
In addition to the routine programme, in NHS Lothian Board area only, pre-natal screening for cystic fibrosis was offered for some years. The programme was developed locally following a research project in the area several years ago, but it has recently been discontinued.
There is variation in the provision of ultrasound fetal anomaly screening services between NHS Boards in Scotland so that at the present time only about 60% of maternity units offer 18-20 week anomaly scanning. However, the Scottish Executive will be reviewing their policy on this issue in the light of the recommendations from the Health Technology Assessment carried out in Scotland by NHS Quality Improvement Scotland, together with the advice from the National Screening Committee.
Newborn Screening
Parents of all newborn babies in Scotland are offered dried blood spot screening for phenylketonuria ( PKU), congenital hypothyroidism ( CHT) and cystic fibrosis ( CF). Tests for PKU were introduced in 1965, for CHT in 1979 and for CF in February 2003.
There is a single screening laboratory in Glasgow to which all the Guthrie Cards from babies born throughout Scotland are sent for testing.
Recent developments of the screening programme mean that there is now standard information given to all parents across Scotland, standardised consent procedures and common programme standards developed for QA management of the programme, by NHSQIS.
In line with the recommendations from the National Screening Committee, universal newborn hearing screening has been implemented in Scotland. Following on from the two pathfinder sites, where screening was initiated in 2003, the programme was rolled out across Scotland during 2005. Genetic testing (for Connexion 26) is available within the SMGC service in Scotland and can be offered to the families of babies with hearing defects, detected by the screening programme, when it is appropriate.
So far no decisions have been taken with respect to introducing screening for haemoglobinopathies in Scotland, as is occurring in England at present. An Expert Group was established to look at this issue and they have submitted their report and recommendations to the Scottish Executive. The Executive will, therefore, give further consideration to the issue and Ministers will decide which approach, universal screening or targeted screening, they feel is appropriate to introduce in Scotland in view of the very different population mix in Scotland compared with England.
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