is an eye disorder characterized by abnormal development of the blood vessels in the retina (retinal telangiectasia). Most affected people begin showing symptoms of the condition in childhood. Early signs and symptoms vary but may include vision loss, crossed eyes (strabismus), and a white mass in the pupil behind the lens of the eye (leukocoria). Overtime, coats disease may also lead to retinal detachment, glaucoma, and clouding of the lens of the eye (cataracts) as the disease progresses. In most cases, only one eye is affected (unilateral). The exact underlying cause is not known but some cases may be due to somatic mutations in the NDP gene. Treatment depends on the symptoms present and may include cryotherapy, laser therapy, and/or surgery. Source: Genetic and Rare Diseases Information Center (GARD), supported by ORDR-NCATS and NHGRI.