Which condition is characterized by a "cherry-red spot" on the macula in infants?

Tay-Sachs disease is characterized by a "cherry-red spot" on the macula in infants. This condition is a genetic disorder caused by a deficiency in the enzyme hexosaminidase A, leading to the accumulation of GM2 gangliosides in the brain and nervous system. As a result, affected infants typically demonstrate developmental delays and neurodegeneration.

The "cherry-red spot" appears in the retina due to the contrast between the pale surrounding retina and the area of the macula, which remains intact while other areas of the retina are affected by the disease. This clinical finding is a pivotal diagnostic indicator, often prompting further evaluation for Tay-Sachs disease, especially in populations with higher carrier rates for this genetic condition.

Other choices do not present with a cherry-red spot in the macula. For example, cystic fibrosis primarily affects the respiratory and digestive systems; Down syndrome may exhibit various physical traits but is not associated with this specific ocular manifestation; while spinal muscular atrophy affects motor neurons and muscle function without causing characteristic retinal findings like a cherry-red spot.