What are rare diseases?
In total rare disease affects around 3.5 million people in the UK, that is approximately 6% of our population.1
- In the UK, a single rare disease may affect as many as 30,000 people or just one individual. The majority of rare diseases affect far fewer people, and some affect less than ten or only a single person in the UK.2
- It is estimated that there are between 6,000 and 8,000 rare diseases in the world.2
- More than 85% of rare diseases are caused by a defect in just one of the 20,000 genes that make up a person’s genetic code.1
- Rare diseases caused by a genetic defect can be inherited i.e. the defect can be passed from parent to child. Inherited diseases may affect several different generations within the same family.1
More information about Rare Disease Day is available at, http://www.rarediseaseday.org
Rare diseases at Moorfields Eye Hospital
Inherited diseases affecting the retina are now the leading cause of registered blindness in working-age adults in England and Wales3.
Moorfields Eye Hospital hosts a tertiary referral service for patients who have rare eye diseases which means people may be referred for care to Moorfields from GPs and other hospitals all around the UK.
Our clinical researchers, along with scientific colleagues at the UCL Institute of Ophthalmology, conduct research studies for a wide range of rare conditions affecting both the front and the back of the eye.
Patients under the care of Moorfields may be eligible (depending on research study criteria) to take part in Moorfields-based clinical research studies, as well as national studies hosted through the National Institute for Health Research (NIHR) BioResource, or the Genomics England 100,000 Genomes Project.
The NIHR also funds a Translational Research Collaboration for Rare Diseases of which “Eye Diseases” is one of 14 specialist themes. The Eye Diseases theme is hosted by our NIHR Moorfields Biomedical Research Centre under the leadership of Prof Graeme Black (Manchester) and Prof Andrew Webster (Moorfields and UCL Institute of Ophthalmology). Currently, the projects within this national programme are exploring detailed phenotyping for:
- Stargardt’s Disease,
- Optic neuropathies (particularly Leber’s Hereditary Optic Neuropathy and Autosomal Dominant Optic Neuropathy)
- Cone Dysfunction Syndromes (particularly Achromatopsia and Blue Cone Monochromacy).
What are our main aims in researching rare eye diseases?
For each rare eye disease we seek to identify which defects, in which genes cause the disease. To do this, we identify families who have a particular rare condition and by comparing the genes in those family members who are affected by the condition with those who are not, we can find the common difference responsible – this is called the ‘genetic origin of the disease’.
Once we know the genetic origin, it is then possible through use of a simple blood test for us to give other similarly affected people, in other families, an accurate diagnosis. Moreover, knowing which gene is responsible for a disease, helps scientists to better understand what drives the disease inside the body which in turn gives them a better chance of developing an effective therapy to treat the condition in the future.