Fig. 6. Mutation in IFT88 rescues limb formation in Shh mutants. (A) At E12.5, Shh mutant embryos are smaller and have a cyclopic eye, proboscis-like facial structure and curly tail. (B) Shh/Ift88^hypo double mutants are of normal size, have separated eyes, partially rescued facial structure and normal looking tail. (C) Ift88^hypo embryos have very mild ventral midline defects and sometimes exencephaly. (D) Shh mutant embryos have only one digit in all four limbs. (E) Shh/Ift88^hypo double mutant limbs and (F) Ift88^hypo mutant limbs display multiple digits.