title: TBX15 mutations cause craniofacial dysmorphism, hypoplasia of scapula and pelvis, and short stature in Cousin syndrome.
abstract: Members of the evolutionarily conserved T-box family of transcription factors are important players in developmental processes that include mesoderm formation and patterning and organogenesis both in vertebrates and invertebrates. The importance of T-box genes for human development is illustrated by the association between mutations in several of the 17 human family members and congenital errors of morphogenesis that include cardiac, craniofacial, and limb malformations. We identified two unrelated individuals with a complex cranial, cervical, auricular, and skeletal malformation syndrome with scapular and pelvic hypoplasia (Cousin syndrome) that recapitulates the dysmorphic phenotype seen in the Tbx15-deficient mice, droopy ear. Both affected individuals were homozygous for genomic TBX15 mutations that resulted in truncation of the protein and addition of a stretch of missense amino acids. Although the mutant proteins had an intact T-box and were able to bind to their target DNA sequence in vitro, the missense amino acid sequence directed them to early degradation, and cellular levels were markedly reduced. We conclude that Cousin syndrome is caused by TBX15 insufficiency and is thus the human counterpart of the droopy ear mouse.
authors.affiliation: Centre for Pediatrics and Adolescent Medicine, Department of Pediatrics, University of Freiburg, 79106 Freiburg, Germany.
authors.forename: Ekkehart
authors.initials: E
authors.lastname: Lausch
authors.forename: Pia
authors.initials: P
authors.lastname: Hermanns
authors.forename: Henner F
authors.initials: HF
authors.lastname: Farin
authors.forename: Yasemin
authors.initials: Y
authors.lastname: Alanay
authors.forename: Sheila
authors.initials: S
authors.lastname: Unger
authors.forename: Sarah
authors.initials: S
authors.lastname: Nikkel
authors.forename: Christoph
authors.initials: C
authors.lastname: Steinwender
authors.forename: Gerd
authors.initials: G
authors.lastname: Scherer
authors.forename: Jürgen
authors.initials: J
authors.lastname: Spranger
authors.forename: Bernhard
authors.initials: B
authors.lastname: Zabel
authors.forename: Andreas
authors.initials: A
authors.lastname: Kispert
authors.forename: Andrea
authors.initials: A
authors.lastname: Superti-Furga
mesh_terms: D001827:Body Height / Q000235:genetics*; D002648:Child; D019465:Craniofacial Abnormalities / Q000000981:diagnostic imaging / Q000235:genetics*; D005260:Female; D006801:Humans; D009154:Mutation; D020125:Mutation, Missense; D010388:Pelvis / Q000000981:diagnostic imaging / Q000473:pathology*; D011859:Radiography; D012540:Scapula / Q000000981:diagnostic imaging / Q000473:pathology*; D013577:Syndrome; D020825:T-Box Domain Proteins / Q000235:genetics* / Q000378:metabolism; D055815:Young Adult
chemical_list: D020825:T-Box Domain Proteins; C523795:TBX15 protein, human