Inherited retinal diseases, or IRDs, are rare eye disorders caused by an inherited gene mutation. Depending on the particular IRD, people can gradually lose their vision or they can be born with vision problems. For a great overview of IRDs, visit our Resources page or visit asharedvision.com.
Leber congenital amaurosis, or LCA, is a particular IRD that causes the cone and rod cells in the retina to degenerate. People with LCA inherit a gene mutation from both parents. They are born with severe vision loss and eventually they become completely blind. This is the rare disease for which Sofia Sees Hope was originally founded, and we still work to raise awareness and to help families deal with LCA, along with other IRDs. Get more detail about LCA.
People with different IRDs, such as retinitis pigmentosa (RP) or choroideremia (CHM), experience a more gradual loss of vision. All are rare diseases – LCA occurs in about 1 in 33,000 people. This is why Sofia Sees Hope works to create greater awareness among families, medical professional and researchers, and to help find treatments and cures.
LCA has a variety of symptoms, is often confused with other eye diseases, and can be hard to diagnose. Infants’ eyes may look normal, but they may have unusual eye movement, sensitivity to light, deep-set eyes, or a lack of visual responsiveness. Some children press their eyes with fingers or fists frequently. Some have cataracts. Some have other body systems involved, like kidneys. Low retinal activity can be tested by electroretinogram (ERG) to help determine if a person has LCA, but eye doctors are often unfamiliar with LCA.
The best way to diagnose LCA is with genetic testing to identify the gene mutation that caused it. There are about 24 genes associated with LCA, and a mutation in just one of them can cause blindness. Testing is easy, based on saliva or blood samples. It should be done by an experienced laboratory where genetic counselors can explain test results and recommend next steps.
In the teenage years, LCA symptoms become more obvious. The retina may change color and blood vessels in the eye may become narrow. Vision usually stays about the same, with the ability to count fingers or see bright lights. Some people become more sensitive to light and some become very far-sighted. However, since LCA is rare and not well understood, people can feel isolated, frustrated and helpless. That is why genetic counseling, support services and access to other LCA families are so important.
Sofia Sees Hope recommends that all LCA families participate in a registry to build awareness and stay informed about research. This also helps families connect with medical specialists, advocacy groups, and clinical trial of new treatments that might help cure LCA.