Skip to content

Eye diseases

Retinal dystrophy

distrofia coroidea
Hereditary and minority eye diseases
Over 300 genes associated to these disorders.
Advances in genetic diagnosis and future treatments.

What is retinal dystrophy?

Retinal dystrophy is a hereditary disease of the retina that affects its outermost layers, primarily damaging the photoreceptor cells (a type of light-sensitive neurones) and the pigment epithelium (responsible for feeding the photoreceptors). In some dystrophies, there might also be alterations in the vitreous gel that fills eyeball and is in contact with the retina.

There are round twenty different retinal dystrophies that might appear only in the eye or be associated to syndromes affecting several organs.  Some of the main ones are:

  • Achromatopsia
  • Leber congenital amaurosis
  • Choroideremia
  • Cone dystrophy
  • Cone-rod dystrophy
  • Best disease
  • Stargardt disease
  • Retinitis pigmentosa
  • Retinoschisis
  • Stickler Syndrome
  • Usher Syndrome
  • Familial exudative vitreoretinopathy

Retinal dystrophies might often have overlapping symptoms and very subtle differences between them, so it can be difficult to tell them apart precisely. The Miranza clinics (link) employs specialists in these “rare” or minority diseases (present in around 1 in every 3,000 people) and we offer a genetic diagnosis service at the IMO Grupo Miranza lab to supplement the clinical diagnosis and put a name to each disease.

The symptoms you might experience vary depending on each retinal dystrophy and its degree of evolution. Whether it affects your central and/or peripheral vision will depend on the type of photoreceptor cell damaged by the disease: in the first case, the cones (concentrated in the centre of the retina and needed to make out details and colours) or, in the second, the rods  (distributed around the retina and responsible for night vision). Therefore, chromatic alterations or poor night vision are also common in some dystrophies, as well as other symptoms such as dazzle and extreme sensitivity to light, or flashes.

Retinal dystrophies are genetic and, therefore, hereditary (they do not depend on external or acquired factors). There are now over 300 genes identified as being associated to these disorders, and research remains in progress to find others yet to be discovered, which is where we come in at the Miranza R&D+i Area (link to research) through the research projects channelled by the IMO Foundation.

The mutations in these genes mean that the retinal cells do not work properly, leading to their degeneration. A given gene might be associated to several retinal dystrophies and, in turn, a retinal dystrophy might be due to different genes.

Retinal dystrophies still have no effective cure, although there are several promising lines of research in which Miranza is involved, such as gene and cell therapies or artificial vision through retinal chips.

Until these advances are available to patients, it is important to visit the ophthalmologist to:

  • Correctly diagnose the disease, from a clinical and genetic viewpoint. Without a genetic diagnosis –i.e. without knowing the gene and mutation responsible for the disease in each patient–, it might be difficult to determine its inheritance pattern or visual prognosis, and no gene therapies (personalised treatments) will be possible in the future.
  • Detect and treat associated eye complications early on, such as cataracts, retinal detachment, or macular oedema.
  • Provide a visual rehabilitation programme in the Poor Vision Area, greater independence.