Inherited retinal degenerations, also called inherited retinopathies refer to a group of often rare conditions in which defects in genes lead to photoreceptor cell death and associated vision loss.
These conditions, among others,include :
Bardet-Biedel syndrome
Best disease
Blue Cone Monochromacy
Choroideremia
Cone-rod dystrophy
Leber Hereditary Optic Neuropathy (LHON)
Leber Congenital Amaurosis (LCA)
Retinitis Pigmentosa (RP)
Retinoschisis
Rod-cone dystrophy
Stargardt Disease
Usher Syndrome
Striving to provide the greatest support and the highest level of clinical care to the IRD community in Ireland, four key goals underpin the Target 5000 programme.
Inherited retinal degenerations (IRDs) are among the most complex of all genetic conditions, involving more than 270 genes. Alongside the many different genes that can cause an IRD (known as your genotype), experiences in terms of age of onset and level of severity of sight loss can also vary greatly from person to person (known as your phenotype). As such, it is often impossible to give an accurate diagnosis by just routine eye examinations and/or imaging. To receive a complete diagnosis, requires genetic testing.
A registry is a central resource cataloguing all those who have a specific medical condition within a geographic area, usually a country. The need for patient registries arises from a desire to have accurate, valid, reliable and timely information about a particular patient group or condition.
This is true for rare diseases, which are often poorly understood and not well documented. As part of Target 5000, a national registry on inherited retinopathies is being established, incorporating both genetic and clinical data.
This data may be used in the future to identify potential eligible participants for clinical trials or approved therapies. Additionally, information captured by this registry can facilitate research and help improve health care services and management.
Target 5000 has established Ireland’s first ophthalmology specific clinical genetics service for participants. This includes the appointment of clinical genetic experts to the programme who can interpret and deliver important genetic information back to people and their families.
Target 5000 also aims to ensure the availability of resources at clinics to provide details on supports and services available or up to date information on research advances and therapeutic development.
For approximately 65% of cases, genetic testing in inherited retinal degenerations is inconclusive. However, we can now dig deeper into the genome in the hope of finding unknown causes of disease. These may be mutations in new genes but also undiscovered mutations outside the protein-coding parts of a gene, known as intronic regions.
Under the ‘Discovery Arm’ of Target 5000, Fighting Blindness is funding scientists in Ireland and abroad to greater understand the mechanisms behind retinal disease and to find as yet unknown genetic causes of retinal degenerations.