IFT122 is a component of the intraflagellar transport complex A (IFT-A), essential for retrograde ciliary transport and ciliary protein trafficking 12. It plays a critical structural role connecting the core and peripheral subcomplexes of IFT-A 2. IFT122 is required for primary cilia assembly and maintenance during embryonic development, particularly in neural tube and limb patterning 3. The protein acts as a negative regulator of Sonic Hedgehog signaling by facilitating ciliary entry of signaling components like Smoothened 2. IFT122 mutations cause cranioectodermal dysplasia (CED/Sensenbrenner syndrome), an autosomal-recessive ciliopathy characterized by craniofacial, skeletal, and ectodermal abnormalities 45. Disease-associated missense mutations impair ciliary protein trafficking without completely preventing cilia formation, reducing ciliary localization of regulatory proteins like ARL13B and INPP5E 26. IFT122 mutations also associate with retinitis pigmentosa, where defective intraflagellar transport impairs photoreceptor opsin trafficking and causes progressive retinal degeneration 7. Complete IFT122 loss causes embryonic lethality with severe developmental defects including neural tube and limb malformations 3.