However, certain limitations have been reported in the KC and KPC models such as an ‘extra’-pancreatic phenotype (due to leaky expression of the Pdx1-Cre allele in other tissues such as in the skin, the oral mucosa, the perianal, gastric and adrenal regions) (Hingorani et al., 2003, 2005; Rachagani et al., 2012b). Here, PDX1 is linked to keratoconus.