title: A case of boomerang dysplasia with a novel causative mutation in filamin B: identification of typical imaging findings on ultrasonography and 3D-CT imaging.
abstract: Boomerang dysplasia is a rare lethal osteochondrodysplasia characterized by disorganized mineralization of the skeleton, leading to complete nonossification of some limb bones and vertebral elements, and a boomerang-like aspect to some of the long tubular bones. Like many short-limbed skeletal dysplasias with accompanying thoracic hypoplasia, the potential lethality of the phenotype can be difficult to ascertain prenatally. We report a case of boomerang dysplasia prenatally diagnosed by use of ultrasonography and 3D-CT imaging, and identified a novel mutation in the gene encoding the cytoskeletal protein filamin B (FLNB) postmortem. Findings that aided the radiological diagnosis of this condition in utero included absent ossification of two out of three long bones in each limb and elements of the vertebrae and a boomerang-like shape to the ulnae. The identified mutation is the third described for this disorder and is predicted to lead to amino acid substitution in the actin-binding domain of the filamin B molecule.
authors.affiliation: Department of Obstetrics and Gynecology, Yamagata University Faculty of Medicine, Yamagata, Japan. stsutsumi@med.id.yamagata-u.ac.jp
authors.forename: Seiji
authors.initials: S
authors.lastname: Tsutsumi
authors.forename: Ayako
authors.initials: A
authors.lastname: Maekawa
authors.forename: Miyuki
authors.initials: M
authors.lastname: Obata
authors.forename: Timothy
authors.initials: T
authors.lastname: Morgan
authors.forename: Stephen P
authors.initials: SP
authors.lastname: Robertson
authors.forename: Hirohisa
authors.initials: H
authors.lastname: Kurachi
mesh_terms: D000328:Adult; D019943:Amino Acid Substitution; D003285:Contractile Proteins / Q000235:genetics* / Q000378:metabolism; D004392:Dwarfism / Q000000981:diagnostic imaging / Q000196:embryology* / Q000235:genetics*; D019066:Facies; D017809:Fatal Outcome; D005260:Female; D064448:Filamins; D006801:Humans; D021621:Imaging, Three-Dimensional; D007231:Infant, Newborn; D008297:Male; D008840:Microfilament Proteins / Q000235:genetics* / Q000378:metabolism; D009154:Mutation; D010009:Osteochondrodysplasias / Q000000981:diagnostic imaging / Q000196:embryology* / Q000235:genetics*; D011247:Pregnancy; D011263:Pregnancy Trimester, Third; D020033:Protein Isoforms / Q000235:genetics / Q000378:metabolism; D012131:Respiratory Insufficiency / Q000209:etiology; D047929:Term Birth; D014057:Tomography, X-Ray Computed; D016216:Ultrasonography, Prenatal
chemical_list: D003285:Contractile Proteins; C578662:FLNB protein, human; D064448:Filamins; D008840:Microfilament Proteins; D020033:Protein Isoforms