Achromatopsia 2

Alternative Names

  • ACHM2
  • Colorblindness, Total
  • Rod Monochromatism 2
  • Rod Monochromacy 2
  • RMCH2
Back to search Result
WHO-ICD-10 version:2010

Diseases of the eye and adnexa

OMIM Number

216900

Mode of Inheritance

Autosomal recessive

Gene Map Locus

2q11.2

Description

Achromatopsia is a congenital cone dystrophy characterized by a complete absence of functional cones in the retina. In infancy, patients present with poor visual acuity, pendular nystagmus, severe photophobia, and a complete lack of color perception. Visual acuity generally stabilizes around 20/200, however, nystagmus and photophobia may improve slightly with time.

In the US, achromatopsia occurs with an estimated prevalence of less than 1 in 30,0000. Diagnosis of achromatopsia is based on medical history, color vision testing, and electrophysiologic examination. Genetic testing can confirm the diagnosis. There is no treatment to cure achromatopsia, but in those affected, the remaining vision can be enhanced using different aids. Dark brown or red tinted sunglasses help reduce light intensity and maximize the function of the rods during the day.

Achromatopsia is inherited in an autosomal recessive manner. There are four different genes implicated in the development of different forms of achromatopsia. The CNGA3 (Cyclic Nucleotide Gated Channel, Alpha-3) gene on chromosome 2q is involved in the pathogenesis of achromatopsia 2.

Epidemiology in the Arab World

View Map
Subject IDCountrySexFamily HistoryParental ConsanguinityHPO TermsVariantZygosityMode of InheritanceReferenceRemarks
216900.1.1United Arab EmiratesFemaleYesNo Reduced visual acuity; Photophobia; Ny...NM_001298.3:c.847C>T, NM_001298.3:c.1190G>THeterozygousAutosomal, RecessiveAhuja et al. 2008
216900.1.2United Arab EmiratesMaleYesNo Reduced visual acuity; Photophobia; ...NM_001298.3:c.847C>T, NM_001298.3:c.1190G>THeterozygousAutosomal, RecessiveAhuja et al. 2008 Brother of 216900.1....
216900.1.3United Arab EmiratesFemaleYesYes Reduced visual acuity; Photophobia;...NM_001298.3:c.1190G>THomozygousAutosomal, RecessiveAhuja et al. 2008 First cousin, once r...
216900.1.4United Arab EmiratesMaleYesYes Reduced visual acuity; Photophobia;...NM_001298.3:c.1190G>THomozygousAutosomal, RecessiveAhuja et al. 2008 First cousin, once r...
216900.1.5United Arab EmiratesFemaleYesYes Reduced visual acuity; Photophobia...NM_001298.3:c.1190G>THomozygousAutosomal, RecessiveAhuja et al. 2008 First cousin, once r...
216900.2.1United Arab EmiratesMaleYesNo Reduced visual acuity; Photophobia; ...NM_001298.3:c.847C>THomozygousAutosomal, RecessiveAhuja et al. 2008
216900.2.2United Arab EmiratesMaleYesNo Reduced visual acuity; Photophobia; ...NM_001298.3:c.847C>THomozygousAutosomal, RecessiveAhuja et al. 2008 Brother of 216900.2....
216900.3United Arab EmiratesMale AchromatopsiaNM_001298.3:c.1114C>THomozygousAutosomal, RecessiveKhan. 2020
216900.4United Arab EmiratesMale AchromatopsiaNM_001298.3:c.1495C>T, NM_001298.3:c.967G>CCompound heterozygousAutosomal, RecessiveKhan. 2020
216900.5United Arab EmiratesMale AchromatopsiaNM_001298.3:c.847C>T, NM_001298.3:c.1190G>TCompound heterozygousAutosomal, RecessiveKhan. 2020
216900.6United Arab EmiratesMale AchromatopsiaNM_001298.3:c.847C>THomozygousAutosomal, RecessiveKhan. 2020
216900.7United Arab EmiratesFemale AchromatopsiaNM_001298.3:c.1457G>AHomozygousAutosomal, RecessiveKhan. 2020
216900.G.1Saudi ArabiaUnknownYesYes Visual impairmentNM_001298.3:c.556C>THomozygousAutosomal, RecessivePatel et al, 2018 3 family members

Other Reports

Iraq

Zlotogora (1995) observed that Achromatopsia, which is usually very rare, is relatively frequent among Iraqi Jews.

Morocco

Zlotogora (1995) observed that Achromatopsia, which is usually very rare, is relatively frequent among Moroccan Jews.

© CAGS 2024. All rights reserved.