Single nucleotide variants c.-13G → C (rs17429833) and c.108C → T (rs72466472) in the CLDN1 gene and increased risk for familial colorectal cancer.

Background: The Claudin-1 (CLDN1) protein plays an important role in the function of the tight junction and studies have shown it is aberrantly downregulated in many tumors including colorectal cancer (CRC). The aim of this study was to determine the relationship between four SNVs in the CLDN1 gene [c.-13G → C (rs17429833), c.