At 6 months-of-age, female Ctns KO mice have developed a mild Fanconi syndrome, including a 1.5-fold increased diuresis and significant glucosuria as compared to WT age-matched controls, and kidney cystine accumulation increases considerably during the 6-to-8 months interval18,22,31,32. This evidence concerns the gene CTNS and Fanconi renotubular syndrome.