However, the MCJ-deficiency in DSS-treated mice resulted in the decreased expression of Cldn2 and increased levels of Cldn5 transcripts in the colon, suggesting an effect on tight junction permeability, although results should be interpreted with caution as only differences in concentration and not in localization have been determined. This evidence concerns the gene CLDN5 and hyperinsulinemic hypoglycemia, familial, 4.