Novel COL2A1 variants in Japanese patients with spondyloepiphyseal dysplasia congenita.

Spondyloepiphyseal dysplasia congenita (SEDC) is a multisystemic skeletal disorder caused by pathogenic variants in COL2A1. Here, we report the genotype-phenotype correlations in five Japanese patients with SEDC based on their clinical and radiological findings. All five patients had novel missense variants resulting in glycine substitutions (G474V, G543E, G567S, G594R, and G1170R). Genetic testing is important for early intervention for the extraskeletal complications of SEDC. Spondyloepiphyseal dysplasia congenita (SEDC) (OMIM#183900) is an autosomal dominant chondrodysplasia characterized by disproportionate short stature, abnormal epiphyses, flattened vertebral bodies (skeletal abnormalities), and extraskeletal features, including myopia, retinal degeneration with retinal detachment, and cleft palate. SEDC is caused by a heterozygous variant in the collagen II alpha 1 (COL2A1) gene.