Retinitis Pigmentosa, or RP, is group of rare genetic disorders that cause the cells of the retina to breakdown and not be replaced. When it is present, people may struggle to see at night and have limited peripherial vision. It is an inherited disorder and can result from any harmful change that occurs on any 1 of 50 different genes. The genes that are affected carry proteins to the cells of the retina. Sometimes the proteins that are made are toxic. At other times, they are just abnormal in nature. Either way, the end result is that the eye begins to degenerate.
Facts About Retinitis Pigmentosa
1. The prevalence of Retinitis Pigmentosa is 1 in 4,000 among all age groups.
2. There are about 1.5 million people around the world who have been diagnosed with this disease.
3. People in the 45+ age demographic have an occurrence rate of 1 in 3,195 for the presence of RP.
4. The X linked variety of RP affects men more than women, but all of the other types of this disease have no sex or ethic preferences. Only 5-15% of RP cases are known to be of the X linked variety.
5. To date, more than 50 different genetic defects have been identified to be linked with Retinitis Pigmentosa.
6. More than 30 rare inherited conditions can include RP-type vision loss.
7. About 30-40% of the diagnosed cases of RP are autosomal dominant.
8. 50 to 60% of the instances of RP are autosomal recessive.
9. The X-linked form of RP is the most severe with loss of central vision seen as early as in the third decade of life itself.
10. Most people who will develop RP will start to see symptoms in their 50s or 60s.
11. Because so many RP-causing gene mutations are still unknown, there is about a 50:50 chance that genetic testing will provide a definitive result.
12. By age 40, many people with RP are legally blind, with a severely constricted field of vision.
13. 75,000. That’s the number of people who are diagnosed with RP. The chances of having RP in the general population of the US are higher than any other statistically tracked country in the world today.
14. A randomized, controlled trial of vitamins A and E found that 15,000 IU a day of vitamin A palmitate could slow the course of the condition among adults with typical forms of RP. Just taking 400 IU of Vitamin E daily, on the other hand, appeared to increase the speed of the disease.
15. Researchers estimate that the combination of vitamin A plus a diet that is rich in Omega 3s could provide almost 20 additional years of useful vision for adults who start the regimen in their 30s.
16. If a father is affected with RP, then all sons will be unaffected and all daughters will be carriers.
17. If the mother is the carrier, 1 in 2 sons will be affected and 1 in 2 daughters will be carriers with each pregnancy having the 50% chance.
18. Women can be carriers of the X linked variety, but do not experience serious vision loss if present.
RP was first discovered as a condition in 1857. In addition to the protein issue and cell damage, some people with this rare genetic degenerative disorder may also suffer from damage to the optic nerve itself. The photoreceptors of the rods and cones are both affected. There is no known cure for RP and there isn’t any known treatments to stop the vision loss that occurs progressively when this disease occurs.
What Is the Cause of RP?
Retinits Pigmentosa is generally considered to be a familial inherited genetic disease. There are some cases that have come from a random mutation and are sporadic, without a family history of the disease. It may be diagnosed as early as the teenage years and people with the disorder may not have it initially present when they are born.
To diagnose RP, two vision tests are usually administered. A side vision test will detect defects in the peripheral vision, while a full ophthalmologist exam with electrophysiological testing can help to confirm the diagnosis. Genetic testing may also be successful in discovering the defective gene.
Eat healthy foods. Get exercise when tolerated. See a doctor immediately if you suspect RP. These three steps will be the best current defense against RP.