What is the pathological condition that causes complete color blindness?

Complete color blindness, also known as achromatopsia, is a rare genetic condition caused by mutations in genes responsible for the function of cone photoreceptors in the retina. Individuals with achromatopsia have non-functional or absent cones, leading to an inability to perceive color and resulting in vision that is primarily in shades of gray. This condition often comes with other visual impairments, such as reduced visual acuity and light sensitivity.