X-Linked Incomplete Achromatopsia
What is X-linked incomplete achromatopsia?
X-linked incomplete achromatopsia, also known as blue cone monochromatism (BCM), is a rare inherited vision disorder. Affected individuals have dysfunctioning cones, which are the cells in the eyes responsible for color. Humans have three cones, each of which responds to a certain color (blue, green, and red). In those with BCM, only the blue cone works properly.
What are the symptoms of X-linked incomplete achromatopsia?
Signs and symptoms of this condition include:
- Sensitivity to light
- Impaired color vision
- Low visual acuity
- Fast and uncontrollable eye movements (nystagmus)
What causes X-linked incomplete achromatopsia?
One of two genes is mutated in this condition: either OPN1MW or OPN1LW. Regardless of which gene is impacted, they are both passed down in an X-linked recessive pattern.
How is X-linked incomplete achromatopsia diagnosed?
Doctors will begin to suspect this condition after noticing sensitivity to light, nystagmus, color blindness, and squinting. A family history of the condition is also a strong indicator of BCM. In regard to testing, doctors may utilize ERG testing, 100 Hue test, HHR test, and D-15 test. Psychophysical and electrophysiological testing may also be used.
What are the treatments for X-linked incomplete achromatopsia?
There is no cure for this condition, but visual aids may be helpful for affected individuals.