The Fish
Cystinosis
Cystinosis is caused by mutations in the CTNS gene encoding for the carrier protein cystinosin that has the task to transport cystin out of the lysosomal compartment. A defect of the cystinosin function results in intra-lysosomal cystin accumulation in all cells. First of all the kidneys are affected, starting with proximal tubular damage during the first year of life, followed by end-stage renal failure during mid-childhood. Also the eyes, thyroid, pancreas and muscles are affected. In some older patients also the CNS can be involved.
