Secondly, truncating mutations (frameshift and nonsense) lying between nucleotides (nt) 1–1,997 and nt 3,482–4,740 of the GLI3 gene result in GCPS, whereas alterations affecting the middle third (nt 1,998–3,481) cause primarily PHS (Johnston et al. 2005, 2010). This evidence concerns the gene GLI3 and Greig cephalopolysyndactyly syndrome.