Note: the condition varies from person to person. this essay is a personal experience.

About

Going back to class 10 biology, we studied all the sensory organs in detail, eyes being one of them. Adding only the relevant parts:

There are two types of photoreceptor cells in the retina

1. Rods: responsible for vision in low-light levels.
2. Cones: responsible for vision in high-light levels, color vision, and spatial acuity

Cone dystrophy is simply an absence of cone cells in the retina.

It is broadly divided into 2 groups: 'progressive' & 'stationary'

Symptoms

Various symptoms include:

• Decreased color perception (dyschromatopsia)
• Increased sensitivity to light (photophobia)
• Decreased visual clarity (acuity)
• Rapid, involuntary eye movements (nystagmus).

Causes

The exact underlying mechanism is unknown.

Although, it's mostly genetic. There have also been cases of it sporadically coming out of nowhere though.

Treatment

None so far :(

Personal experience

• I am one of the 'affected out of nowhere' cases, so is my sister. Our genes don't show any dominant or recessive behavior around this subject.
• First diagnosed was my sister, in 2005, subsequently, so was I.
• We suffer from all the symptoms mentioned above.
  • Nystagmus and acuity have improved over the years.
  • Dyschromatopsia & photophobia have remained unchanged.
    • Taking all the preventive measures we can nonetheless
    • My perception: I can see the colors the way normal people see them, I just struggle with labeling them. I may be wrong.
• Tolerated through all the snarky comments made by the school bullies. Used to feel bad, but we move.