Chordin-like 1

This gene encodes an antagonist of bone morphogenetic protein 4. The encoded protein may play a role in topographic retinotectal projection and in the regulation of retinal angiogenesis in response to hypoxia. Alternatively spliced transcript variants encoding different isoforms have been described.^[5]

CHRDL1 plays important roles in processes such as embryonic cell differentiation, osteogenesis, neurogenesis, tumor and metastasis suppression, and retinal formation.^[7][8] The highest expression of this gene is found in the anterior eye segment and retina as well as in the cerebellum and neocortex.^[6] In the neocortex, it peaks at the time of synapse maturation to allow for proper synaptic formation.^[9] Therefore, this gene is important in proper formation of the central nervous system and the eyes.

Mutations in CHRDL1 are associated to Neuhäuser Syndrome, X-linked megalocornea and central corneal thickness.^[10]

Mutations in this gene may cause a variety of effects on the aforementioned processes. One potential outcome of a CHRDL1 mutation is non-syndromic X-linked megalocornea (XMC) that results from either a missense, nonsense, or frameshift mutation of the gene.^[6] XMC is an enlargement of the anterior segments of the eye that may lead to other issues such as cataracts and glaucoma.^[6] Another potential outcome is carcinogenic formation. Since CHRDL1 is a tumor and metastasis suppressor, a mutation in this gene may lead to tumor cell formation.^[8] The most major effect a mutation could have is on synaptic stabilization. Since the gene limits synaptic plasticity, a mutation may cause issues in proper synapse maturation, leading to a variety of neurological disorders.^[9] There is currently a knockout model for this gene that shows disruption may cause altered synaptic events and reduced synaptic GluA2 AMPARs leading to increased plasticity.^[9]