https://en.wikipedia.org/wiki/Sonic_hedgehog
ref - https://www.reddit.com/r/todayilearned/comments/dxzwet/til_there_exists_a_protein_named_sonic_hedgehog/
origin - https://www.pipiscrew.com/?p=15927 there-exists-a-protein-named-sonic-hedgehog
https://en.wikipedia.org/wiki/Sonic_hedgehog
ref - https://www.reddit.com/r/todayilearned/comments/dxzwet/til_there_exists_a_protein_named_sonic_hedgehog/
origin - https://www.pipiscrew.com/?p=15927 there-exists-a-protein-named-sonic-hedgehog