Sonic hedgehog

This article is about the sonic hedgehog gene and proteins. For information on the Sega game, see Sonic the Hedgehog.

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Sonic hedgehog (shh) is one of three proteins in the hedgehog (Hgg) family, the others being desert hedgehog (dhh) and indian hedgehog (ihh).

Mutations in the human sonic hedgehog gene (SHH) cause holoprosencephaly (HPE).

The hedgehog family got its name for the appearance of the mutant phenotype which causes the embryo to be covered with small pointy projections, much like a hedgehog. The first two discovered, desert and indian, were named for species, while sonic was named for the Sega Genesis character Sonic the Hedgehog.