Several genes, including interleukin 1 beta, cadherin 11, negative regulator of ubiquitin-like protein 1, collagen type XXVII alpha 1 chain, and hepatocyte growth factor, have been linked to the familial manifestation of KC, with a handful of mutations identified (Nowak & Gajecka, 2011). This evidence concerns the gene HGF and keratoconus.