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Updated: Jun 19, 2026

A Phenotyping Regimen for Genetically Modified Mice Used to Study Genes Implicated in Human Diseases of Aging
Published on: July 14, 2016
Renal phenotype of the cystinosis mouse model is dependent upon genetic background
Nathalie Nevo1, Marie Chol, Anne Bailleux
1Inserm, U574, Hôpital Necker-Enfants Malades, Paris, France.
Background:
Cystinosis is caused by mutations in CTNS that encodes cystinosin, the lysosomal cystine transporter. The most severe and frequent form is characterized by a proximal tubulopathy that appears around 6 to 12 months of age. In the absence of treatment, end-stage renal disease is reached by 10 years. Ctns(-/-) mice of a mixed 129Sv x C57BL/6 genetic background show elevated renal cystine levels; however, proximal tubulopathy or end-stage renal disease is not observed.
Methods:
As renal phenotype can be influenced by genetic background, we generated congenic C57BL/6 and FVB/N Ctns(-/-) mice and assayed renal lesions and function by histological and biochemical studies.
Results:
C57BL/6 Ctns(-/-) mice showed significantly higher renal cystine levels than the FVB/N strain. Moreover, C57BL/6 mice presented with pronounced histological lesions of the proximal tubules as well as a tubulopathy and progressively developed chronic renal failure. In contrast, renal dysfunction was not observed in the FVB/N strain.
Conclusions:
Thus, the C57BL/6 strain represents the first Ctns(-/-) mouse model to show clear renal defects. In addition to highlighting the influence of genetic background on phenotype, the C57BL/6 Ctns(-/-) mice represent a useful model for further understanding cystinosin function in the kidney and, specifically, in the proximal tubules.
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