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Eye Diseases of Retina: Color-Blindness, Retinitis Pigmentosa, Age-Related Macular Degeneration


Credit: Rizzo

Our two human eyes are the windows to the world around us. They guide us to the important and significant in our immediate environment and help us avoid dangers and our eyes can lead us astray. When the eyes are blinded the other senses of hearing, taste and smell become more predominant.
Read more about how 3 retinal diseases damage the eyes.
 
Here know 3 important retinal eye diseases 


1. Color-Blindness: Related to Deficiencies of Certain Chemicals in the Cones

Biochemical deficiencies cause blindness to colors of of red, blue or green, or combinations of these colors. 

Color blindness is a non-correctable, inherited disease. Color-blindness is related to a genetic defect carried on the X chromosome.

There are 2 "X" chromosomes in females, and only 1 "X" in males of the total of 46 chromosomes which humans have in each cell of their body.

Therefore, colorblindness is more common in males than females because males have only 1 X chromosome and if there is a defect on that X it will show up. Females with 2 X chromosomes, could have an error in 1 X compensated for by a good gene for normal vision on the other X chromosome. A colorblind female would have both X chromosomes with a defective gene for colorblindness.


2. Retinitis pigmentosa is a Disease Characterized by Rod and Cone Degeneration as shown in the microscopic photo above. There is progressive loss of vision with total blindness as rods and cones degenerate. Compare the right and left sides of the photo to see the normal integrity of the retina and the diseased retina.

3. In Age-Related Macular Degeneration (AMD), the Macula (Fovea), which contains the highest concentration of cones and has the greatest visual acuity, shows cell degeneration and progressive loss of central vision over a period of several years. AMD is a disease that is genetically controlled and most often appears in middle-aged people and beyond. AMD can lead to total blindness over a period of many years.


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