SOX9 dimerization domain mutation mimicking type 2 collagen disorder phenotype.
The classification of bone dysplasia has relied on a clinical/radiographic interpretation and the identification of specific genetic alterations. The clinical presentation of the SOX9 mutation and type 2 collagen disorders overlap with the Pierre-Robin sequence and talipes equinovarus, but the former is often accompanied by the bent long bones. In its milder form, the SOX9 mutation is not necessarily associated with the bent long bones. Here, we report a patient with the Pierre-Robin sequence and talipes equinovarus who did not exhibit either bent long bones or scapular hypoplasia; thus, this patient was instead classified as having a type 2 collagen disorder. Despite this phenotypic presentation, the proposita was found to have a de novo SOX9 mutation. The peculiar location of the mutation within the dimerization domain might account for the relatively mild phenotypic effect of the SOX9 mutation to a degree that is compatible with a clinical diagnosis of type 2 collagen disorder, except for a developmental delay. We concluded that mutations in SOX9 can mimic a type 2 collagen disorder-like phenotype.
Department of Pediatrics, Keio University School of Medicine, Tokyo, Japan.
Toshiki
T
Takenouchi
Department of Pediatrics, Keio University School of Medicine, Tokyo, Japan.
Yohei
Y
Matsuzaki
Department of Orthopedic Surgery, National Rehabilitation Center for Children with Disabilities, Japan.
Kazuka
K
Yamamoto
Department of Orthopedic Surgery, Tokyo Metropolitan Kita Medical & Rehabilitation Center for the Handicapped, Japan.
Keisuke
K
Kosaki
Center for Medical Genetics, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, 160-8582, Tokyo, Japan.
Chiharu
C
Torii
Department of Pediatrics, Keio University School of Medicine, Tokyo, Japan.
Takao
T
Takahashi
Center for Medical Genetics, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, 160-8582, Tokyo, Japan. Electronic address: kkosaki@z3.keio.jp.
Kenjiro
K
Kosaki
D001665:Binding Sites / Q000235:genetics; D002675:Child, Preschool; D003095:Collagen Diseases / Q000175:diagnosis / Q000235:genetics*; D024043:Collagen Type II / Q000235:genetics*; D004252:DNA Mutational Analysis; D002658:Developmental Disabilities / Q000175:diagnosis / Q000235:genetics*; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D020125:Mutation, Missense; D055503:Protein Multimerization; D055758:SOX9 Transcription Factor / Q000737:chemistry / Q000235:genetics*
D024043:Collagen Type II; D055758:SOX9 Transcription Factor; C527932:SOX9 protein, human
Campomelic dysplasia; SOX9; Type 2 collagen disorders