Both small-scale (missense, nonsense, splicing variants, small deletions, small insertions, and indels) and large-scale alterations (gross deletions, gross insertions, and translocations) affecting the GLI3 gene (~300 kb), located on chromosome 7p14.1 can cause GCPS (MIM# 175700) [5] in an autosomal dominant mode of inheritance [1,2,6,7,8]. The gene discussed is GLI3; the disease is Greig cephalopolysyndactyly syndrome.