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The congenital occurrence of dislocated lenses in persons with involvement of other tissues in the body include Marchesani's syndrome, Marfan's syndrome, and now a biochemically discrete syndrome characterized by excretion of homocystine. This latter entity, homocystinuria, is a recent addition to the expanding list of syndromes in which a metabolic disease is found to be attributable to an enzymatic fault in the utilization of one or more amino acids. In this case the enzyme, cystathione synthetase, responsible for the condensation of homocystine and serine, is either absent or inadequate. Homocystine accumulates in the tissues and spills over in the urine. Its presence can be easily detected by the cyanido-nitroprusside test available in most routine chemistry laboratories.
Aside from dislocated lenses, patients with homocystinuria have mental retardation, sparseness of hair, and an abnormal stickiness of platelets which makes them prone to pulmonary thromboembolism. [The significance of the latter became apparent recently
C. D. Dislocated Lenses and Homocystinuria. Arch Ophthalmol. 1965;74(4):446–447. doi:10.1001/archopht.1965.00970040448002
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