With respect to IBD which includes CD and UC, it was reported in German population that the IL-17F A7488G (His161Arg, rs763780) gene SNP is not considered as a marker of susceptibility for IBD per se but is associated with increased disease activity [21], whereas in Chinese population it was demonstrated that the IL-17F A7488G (His161Arg, rs763780) gene SNP has no effect on susceptibility to DC but is associated with protection to UC [22]. This evidence concerns the gene IL17F and dyskeratosis congenita.