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Achromatopsia type 2

Achromatopsia type 2

OMIM number: 216900

Comments closing date: 05/03/2021

Achromatopsia type 2 is an inherited autosomal
recessive eye condition caused by mutations in
the CNGA3 gene on chromosome 2. Several other
types of achromatopsia are caused by mutations
other genes. This application relates to type 2.
Achromatopsia is present from birth causing
nystagmus (wobbly eyes) with no central vision,
extreme painful light sensitivity (day blindness)
which worsens vision and causes narrowing of the
pupil and eyes to “screw up” in daylight. Children
have significantly poor visual acuity (sharpness of
vision) resulting in difficulty recognising faces,
reading and colour blindness. It is generally not
progressive although severity will vary. Affected
children often stay at home with lights low or off.
When appropriate those affected will require
special tinted glasses or lenses to filter out the
light that is uncomfortable. However, over time
such lenses may reduce vision further. Most
children will be registered as partially sighted or
blind. Gene therapy trials of are underway, but not
yet concluded.

Review date: 5 February 2023