Claim: CLDN1 helps create a barrier preventing substances from freely passing through paracellular space and prevents neonatal ichthyosis-sclerosing cholangitis syndrome.
Evidence: Tight junctions represent one mode of cell-to-cell adhesion in epithelial or endothelial cell sheets, forming continuous seals around cells and serving as a physical barrier to prevent solutes and water from passing freely through the paracellular space. Loss of function mutations result in neonatal ichthyosis-sclerosing cholangitis syndrome.