Achromatopsia

Color Blindness.Rod Monochromatism.Stationary Cone Dystrophy

Complete Color-Blindess

Achromatopsia is a hereditary vision disorder that eliminates the ability to see color. In rare instances of complete achromatopsia, achromats are only able to see black, white, and various shades of grey.

"People say to me, 'It must suck to not see color.' I'm thinkin' I wouldn't know, I've never seen it." -Karl Schwonik

Retina Abnormality

Within the retina, there are rod receptors and cone receptors. Cone receptors are typically used in brightly lit, colorful situations. Rod receptors are used in dimly lit situations and provide low-detailed images. Achromats' rod receptors work well, but the cone receptors do not.

Symptoms

  • Reduced Visual Acuity
  • Increased Sensitivity to Light
  • Inability to See Color
  • Nystagmus

Inheritance/Probability

Achromatopsia is rare, recessive, autosomal disorder. There is only 1 achromat per 33,000 births. It is found on the 2q11, 8q21-8q22, 10q24, 14 chromosomes. If both parents carry the gene, each child would have a 25% change of inheriting the disorder, and each child would have a 50% chance of being a carrier.

Achromats

Many achromats can identify color differences in certain lights, especially in low lighting. Some believe they can see certain "colors" better than others. They have typically bad general sight.

Incomplete Achromatopsia

99% of color blind people have incomplete achromatopsia, meaning they can see some hues but frequently confuse color wavelengths. Red-green color blindness and blue-yellow color blindness are the most common forms. Red-green makes up 75% of cases. These people struggle with green, red, and brown. People suffering with blue-yellow color blindness struggle with colors like blue, green, yellow, and violet. Incomplete achromatopsia is a sex-linked disorder.

Treatment

There is no cure for achromatopsia. Many achromats need use of dark tinted glasses for light sensitivity. Wide-lens, padded sunglasses are used for outdoors activities.
A Story of Achromatopsia

Pingelap

The chance of inheriting Achromatopsia is much higher on this island due to severe inbreeding. Almost 30% of the island inhabitants are carriers, with 5-10% being affected.
Big image

John Dalton

Scientist John Dalton wrote the first known scientific paper on color blindness because he was color blind himself. He lived his whole life believing he had colored fluid in his eyes.

Medical Research

There is little to no current research for achromatopsia.