Compound heterozygous variants in the SEC24D gene cause Cole-Carpenter syndrome type 2 or osteogenesis imperfecta. Cole-Carpenter syndrome type 2 is characterized by bone fragility with craniosynostosis, ocular proptosis, hydrocephalus, and distinctive facial features. Patients are diagnosed with osteogenesis imperfecta when syndromic or dysmorphic features are not observed. Six families reported thus far, 3 families were diagnosed with Cole-Carpenter syndrome type 2 and the other 3 families were diagnosed with osteogenesis imperfecta. The SEC24D-related disorder is inherited in an autosomal recessive manner.
SEC24D