Cystinosis is an autosomal recessive lysosomal storage disorder caused by CTNS 
gene mutations. The CTNS gene encodes the protein cystinosin, which transports 
free cystine from lysosomes to cytoplasm. In cases of cystinosin deficiency, 
free cystine accumulates in lysosomes and forms toxic crystals that lead to 
tissue and organ damage. Since CTNS gene mutations were first described, many 
variations have been identified that vary according to geographic region, 
although the phenotype remains the same. Cystinosis is a hereditary disease that 
can be treated with the cystine-depleting agent cysteamine. Cysteamine slows 
organ deterioration, but cannot treat renal Fanconi syndrome or prevent eventual 
kidney failure; therefore, novel treatment modalities for cystinosis are of 
great interest to researchers. The present review aims to highlight the 
geographic differences in cystinosis-specifically in terms of its genetic 
aspects, clinical features, management, and long-term complications.