WHAT IS RETINITIS PIGMENTOSA Retinitis pigmentosa, or RP, is a group of genetic eye conditions. In the progression of symptoms for RP, night blindness generally precedes tunnel vision by years or even decades. Many people with RP do not become legally blind until their 40s or 50s and retain some sight all their life. Others go completely blind from RP, in some cases as early as childhood. WHAT CAUSES RETINITIS PIGMENTOSA Retinitis pigmentosa is thought to be caused by defects of certain genes in the body. The defects cause cells in the retina to malfunction and begin to break down. Retinitis pigmentosa is often hereditary (runs in families). If you, or your partner, have retinitis pigmentosa, there may be up to a 50% chance that you may pass it along to your children. WHAT TO EXPECT FROM RETINITIS PIGMENTOSA While your vision during the day may be completely normal, your inability to see in dark conditions is considered “night blindness.” Loss of side vision also makes moving around more difficult, causing noticeable clumsiness from not being able to see objects below and around you. As the outer areas of vision slowly disappear, the condition commonly referred to as “tunnel vision” occurs. Many people retain a wide enough scope of useful vision for a long period of time. In some cases, central vision may be affected first, making detail work difficult, such as reading or threading a needle. This is referred to as macular dystrophy, because the central area of the retina, called the macula, is affected.