In approximately half of individuals with Down syndrome, an higher than normal number of vessels cross the optic disc margin. Investigator hypothesize that early retinal vessel branching occurs due to inhibition of angiogenesis by triplet overexpression of endostatin, an angiogenesis inhibitor encoded on chromosome 21. Since angiogenesis is critical in the development of eyes and other organs angiogenesis depended (specially kidney, brain, and recently described lungs and heart), early branching of retinal vessels at the level of the optic disc would also likely result in abnormal renal and other organs development in these individuals. Investigator wish to determine whether observation of optic disc vessels may serve as an indicator of elevated endostatin levels and other angiogenesis-dependent organs anomalies.