Retinitis Pigmentosa
Meet Marjolein and Mark. They expect a child within a month. As of recently, Mark is suffering from Retinitis Pigmentosa, an eye disease. As long as he can remember he has problems with night blindness, but since a couple of years it has become worse and worse. There is big chance he will be totally blind in 20 years. Mark’s mother also has Retinitis Pigmentosa: it is an inheritable disease. Marjolein and Mark are both eager to know whether their child will also suffer from the eye disease.
What is Retinitis Pigmentosa?
Retinitis Pigmentosa (RP) is the collective noun for a group of inheritable diseases to the retina. The rod cells in the eyes are damaged. Hereby RP patients have poor vision in the dark (night blindness). Gradually the retina deteriorates and vision decreases. Eventually this can cause tunnel vision and blindness. So far no effective medicine has been developed.
Genetic Research
Marjolein and Mark request help from geneticist Dr. Van Steveninck. He will lead the investigation and is going to figure out to which risks the unborn child is exposed. In this quest he could use some help.
Exercise 1
Patients with RP have damaged rod cells in their eyes. At first, the rod cells are totally intact.
How could the damaged rod cells in patients cause poor vision at night?