Home > D. General pathology > Genetic and developmental anomalies > Johanson-Blizzard syndrome
Johanson-Blizzard syndrome
MIM.243800 15q15-q21.1
Saturday 11 February 2006
Definition: Johanson-Blizzard syndrome (JBS) is a rare autosomal recessive condition characterized by pathognomonic facies and a constellation of other features most notably exocrine pancreatic insufficiency, oligodontia, growth retardation, hearing loss, mental retardation, scalp defects, hypothyroidism and imperforate anus.
Synopsis
short stature
low birth weight
failure to thrive
situs inversus
craniofacial anomalies
- microcephaly
- midline skin dimples over anterior/posterior fontanelles
- hearing loss, sensorineural
- cystic dilatation of cochlea and vestibulum
- strabismus
- cutaneolacrimal fistulae
- lacrimal puncta aplasia
- hypoplastic alae nasi
- beaked nose
- hypoplastic deciduous teeth
- absent permanent teeth
cardiovascular malformations
small nipples
absent areolae
exocrine pancreatic insufficiency
- pancreatic acinar cells immature appearance (17378628)
- pancreatic microlobules separated by loose fibrous tissue (17378628)
- extensive pancreatic periductal fibrosis (17378628)
imperforate anus
anteriorly placed anus
neonatal cholestatic liver disease (18553553)
- liver fibrosis
- portal hypertension
genital anomalies
- micropenis
- hypospadias
- clitoromegaly
- cryptorchidism
- double vagina
- septate vagina
- urethrovaginal fistulae
hydronephrosis
calicectasis
delayed bone age
joint laxity
fifth finger clinodactyly
transverse palmar crease
cafe-au-lait spots
scalp aplasia cutis congenita
transverse palmar crease
blonde, sparse scalp hair
frontal upsweep
extension of lateral hairline onto forehead
’Unruly’ scalp hair
anasarca
edema (hands and feet)
mental retardation (2/3 patients)
hypotonia
hypothyroidism (30% patients)
diabetes mellitus
low total serum protein
hypocalcemia
intestinal malabsorption
Etiology
germline mutation in the ubiquitin-protein ligase E3 component N-recognin 1 gene (UBR1) (MIM.605981)
References
Al-Dosari MS, Al-Muhsen S, Al-Jazaeri A, Mayerle J, Zenker M, Alkuraya FS. Johanson-Blizzard syndrome: Report of a novel mutation and severe liver involvement. Am J Med Genet A. 2008 Jun 13. PMID: 18553553
Hoffman WH, Lee JR, Kovacs K, Chen H, Yaghmai F. Johanson-blizzard syndrome: autopsy findings with special emphasis on hypopituitarism and review of the literature. Pediatr Dev Pathol. 2007 Jan-Feb;10(1):55-60. PMID: 17378628