Norrie disease: The rare genetic disorder that makes people go blind and deaf

A close-up of a baby's eye and nose. The eye is blue. .

Disease name: Norrie disease

Affected populations: Norrie disease is an extremely rare, inherited genetic disorder that causes vision loss and was first described in Denmark in 1927. The exact incidence of Norrie disease in the population is unknown, but around 500 cases have been reported worldwide. The disease mainly affects males, and when females do develop it, they tend to experience milder symptoms.