question: Which are the different homologs or family members of the hedgehog proteins in mammals?
answer: Hedgehog (Hh) signaling proteins stimulate cell proliferation, differentiation, and tissue patterning at multiple points in animal development. A single Hh homolog is present in Drosophila, but three Hh homologs, Sonic hedgehog (Shh), Indian hedgehog (Ihh) , and Desert hedgehog (Dhh), are present in mammals.