AP4E1 and learning disability: Though Ap4e1 does not have an established role in cilia, the predicted protein interaction with OCRL1 is suggestive that Ap4e1 may be involved in ciliary assembly as OCRL1 is known to be involved in primary ciliary assembly and mutations in OCRL1 result in congenital cataracts, renal abnormalities, and learning disabilities, a ciliopathy syndrome called Lowe syndrome45.