Complete achromatopsia (type 2) and Incomplete achromatopsia
Achromatopsia (ACHM) is a rare vision disease that affects approximately one in 30,000 people. This pathology damages certain photoreceptor cells of the retina (specifically the cones) in a way that has serious consequences on vision.
Most individuals who suffer from it have total achromatopsia, with complete absence of activity in all three types of cones. Rarely, incomplete forms of the disease are found with similar, but generally less severe, symptoms.
It is currently known that there are up to 6 genes related to this pathology and about 90% of cases of achromatopsia are due to alterations in the CNGA3 and CNGB3 genes.
Symptoms
Patients with ACHM have poor visual acuity, photophobia and nystagmus (rapid involuntary eye movements) and are unable to distinguish colors. Nystagmus usually appears after birth or in early childhood.
Since photoreceptor function is impaired almost from birth there is no true progression of symptoms over time.
Prevention
No approved therapy is available. Treatment is symptomatic and includes the use of lenses or glasses with special filters to reduce photophobia, improve visual acuity and prevent light damage to the retina. Patients must be followed up by ophthalmologists for the rest of their lives.
Genes analyzed
