hey guys..correct me if i am wrong..but with homocystinuria..you have an elevation in cysteine and decrease in methionine due to the defiency in methionine synthase.

cystinuria is the inherited defect where there is a renal tubular defect and you have elevated levels of cysteine, ornithine, lysine and arginine...people with this defect are predisposed to having kidney stones.