The Genetics Behind Kjer's Optic Atrophy

Kjer's disease is a very rare genetic disorder that is transmitted in an autosomal dominant (versus autosomal recessive or X-linked) fashion.  Autosomal dominant, meaning a person with Kjer's has a 50% chance (with each pregnancy) of having a baby with the disease.  The gene responsible for Kjer's disease is located on chromosome 3.  The disease symptoms may be present by one year of age, although most children do not show vision loss until at least four years of age.  In my case, vision loss became evident on an elementary school screening.  In certain cases, vision loss may not be evident until adulthood.  Severity of the vision loss can vary amongst family members.  Both male and female offspring have the same chance of getting the gene defect.  Researchers have located many different OPA1 gene mutations.  As already stated, the disease is considered to be very rare, with an incidence of 1:10,000 in people of Danish descent, and 1:50,000 of non-Danish.