In a study of SEDC, most variants in COL2A1 were heterozygous missense variants which resulted in a glycine substitution in the triple‐helical domain of the type II procollagen chain, and glycine‐to‐serine substitutions were the most common (Terhal et al., 2015). Here, COL2A1 is linked to spondyloepiphyseal dysplasia congenita.