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Related to monochromasia: monochromatic
ach·ro·ma·top·si·a, achromatopsy (ă-krō'mă-top'sē-ă, a-krō'mă-top-sē), [MIM*216900, MIM*262300 & MIM*603096]
The complete form of achromatopsia, characterized by severe deficiency of color perception, associated with nystagmus, photophobia, reduced visual acuity, and "day blindness"; is of autosomal recessive inheritance. One form, Achromatopsia type 1, maps to chromosome 14. Achromatopsia type 2 is caused by mutation in the cone photoreceptor cGMP-gated cation channel, alpha-subunit 3 gene (CNGA3) on chromosome 2q. Achromatopsia type 3 is caused by mutation in the CNGB3 on 8q.
[G. a- priv. + chrōma, color, + opsis, vision]