What are the symptoms of IRDs?

The symptoms experienced by individuals differ depending on the type of photoreceptors affected.

• Retinitis pigmentosa (RP) causes difficulties with vision in dim light (‘night blindness’) and constriction of visual fields. As it progresses, central vision may become affected, with severe cases resulting in complete or nearly complete blindness.
• Macular dystrophies cause problems with central vision. However, there is a large amount of variability, with some IRD patients remaining asymptomatic until late in life.

Do IRDs only affect the eyes?

IRDs refer to a large group of genetic disorders that affect the retina. In most cases, the inherited gene defect only affects the eyes.

Sometimes, other parts of the body are also affected, and this is called syndromic RP. An example of syndromic RP is Usher syndrome, which causes both RP and hearing loss. Other examples include Refsum, Alström and Laurence-Moon-Bardet-Biedl (LMBB) syndromes.