5. IDENTIFYING AND PREVENTING RARE DISEASES
UK Strategy Commitments
9. Continue to work with the UK National Screening Committee to ensure that the potential role of screening in achieving earlier diagnosis is appropriately considered in the assessment of all potential new national screening programmes and proposed extensions to existing programmes.
10. Initiate action to ensure carrier testing approved by the appropriate commissioning bodies, where the associated molecular tests are evaluated and recommended by UKGTN (UK Genetic Testing Network) is accessible for at risk relatives.
Where we are now
Many rare diseases are present at birth and are either caused by genetic factors (for example sickle cell disease) or deficiencies or exposures to substances around the time of conception or during pregnancy (for instance, spina bifida is associated with a folic acid deficiency around conception and early pregnancy).
A World Health Organisation report in 2010 found that birth defects "…can be life-threatening, result in long-term disability, and negatively affect individuals, families, health-care systems and societies." and that early diagnosis and action can prevent complications and illness.
Screening has an important role in allowing early diagnosis of some rare diseases and the initiation of early treatment to reduce complications. The Scottish Government is represented in the UK National Screening Committee which makes its recommendations to all 4 Health Departments across the UK.
Potential new national screening programmes are rigorously assessed by the UK National Screening Committee before their introduction to assess the evidence for programmes against a set of internationally recognised criteria covering the condition, the test, the treatment options and the effectiveness and acceptability of the screening programme. This approach is intended to ensure that screening approaches do more good than harm at a reasonable cost. Any proposed extension to existing programmes is similarly assessed.
In NHS Scotland, screening policy is set by the Scottish Government Health Directorates on the advice of the UK National Screening Committee and other appropriate bodies. NSD commissions and co-ordinates important elements of national screening programmes helping to ensure consistent, effective, coordinated national screening programmes for the people of Scotland.
In some circumstances, case finding approaches may provide an alternative approach to the identification of individuals at risk of a specific disease to offer screening and if appropriate treatment.
Newborn Baby Screening
In Scotland, newborn baby screening uses a blood spot test (the Guthrie card) for five conditions: Phenylketonuria, Congenital Hypothyroidism, Cystic Fibrosis, Medium Chain Acyl-CoA Dehydrogenase Deficiency and Sickle Cell Disease.
The Laurie report notes that parents have the option to consent to "…individual tests, all tests, or none of the tests." If parents agree to screening, the blood spot card is retained, for a 12-month period. This consent can be extended beyond 12-months with parent permission. If no permission is given, the card is destroyed.
Retained blood spots have potential anonymous post-test use for "…purposes such as comparing different screening methods and developing new tests." Such usage of the blood spots and the genetic material they contain (dating back to 1965 and containing 2.5 million cards with blood/DNA samples/personal information) was the subject of review, reported on in the Laurie report. This provides a commentary on the storage and potential future uses of the Guthrie cards held in NHS Scotland.
Four National Managed Clinical Networks (NMCNs) provide effective links between the Scottish Newborn Screening Programme and relevant clinical services.
In association with the national pregnancy and newborn screening protocols, counselling is provided to 'at risk' relatives on carrier status if applicable. There is access to genetic testing for at risk relatives in Scotland through the Scottish Genetics Centres.
Within the Scottish Molecular Genetics and Cytogenetics Laboratory Consortium work is focussing on the use of new techniques to allow increased range of genetics panel testing and this is planned to extend to exome sequencing within the next two years.
The Scottish Molecular Genetics and Cytogenetics Laboratory Consortium's current policy is for provision of small Next Generation Sequencing (NGS) devices in all 4 centres. This supports regional subspecialisation within the UKGTN and a distributed pattern of testing close to clinical decision making. Such an approach is sustainable, is considered appropriate to Scotland's geography and fits with the rapid advances in technology. There is close collaboration with Scottish universities.
NHS Education Scotland, National Services Division, the Molecular and Cytogenetics Laboratory and Molecular Pathology Consortia have recently reviewed the future needs for scientists to support future developments in testing and NES is facilitating the implementation of recommendations.
There is an untapped potential for public health services to explore 'upstream' prevention for rare diseases taking into account and acting on social and economic determinants of poor health amongst people with rare diseases.
Suggested Next Steps Emerging from Discussion/Engagement with Stakeholders
- Along with their partners public health specialists in NHS Boards should explore options for appropriate interventions to address determinants of health in rare diseases.
Screening for Rare Disease
- Consider the introduction in Scotland of recommendations from the UK National Screening Committee
- Continue to ensure access for people in Scotland and families to UKGTN approved carrier testing, extending coverage as appropriate.
Email: Paul Currie