title: Johanson-Blizzard syndrome: expanding the phenotype of exocrine pancreatic insufficiency.
abstract: BACKGROUND
  Johanson-Blizzard syndrome (JBS) is a rare autosomal recessive syndrome characterized by dysmorphic nasal alae, ectodermal abnormalities, exocrine pancreatic insufficiency and early growth failure. Most patients are diagnosed by clinical criteria prenatally or in early infancy. Nonsense, frame shift and splice-site mutations of the ubiquitin ligase gene (UBR1) lead to early loss of acinar cells in individuals with JBS.
  
  
  METHODS
  We describe a previously asymptomatic patient with ectodermal dysplasia presenting with sudden onset exocrine pancreatic insufficiency in adolescence. The family reports an identical twin brother with similar symptoms.
  
  
  CONCLUSIONS
  This case illustrates that the phenotypic variability of pancreatic involvement in JBS may be subtle and may not manifest until the second decade of life. We suspect that this mild phenotype results from mutations in UBR1 allowing for partial function.
authors: Division of Gastroenterology, Hepatology, and Nutrition, Nationwide Children's Hospital, The Ohio State University College of Medicine, Columbus, Ohio, USA. kate.ellery@nationwidechildrens.org.
authors: Kate M
authors: KM
authors: Ellery
authors: Steven H
authors: SH
authors: Erdman
mesh_terms: D000015:Abnormalities, Multiple / Q000175:diagnosis / Q000235:genetics; D000293:Adolescent; D001006:Anus, Imperforate / Q000150:complications / Q000175:diagnosis* / Q000235:genetics; D003937:Diagnosis, Differential; D004476:Ectodermal Dysplasia / Q000150:complications / Q000175:diagnosis* / Q000235:genetics; D010188:Exocrine Pancreatic Insufficiency / Q000175:diagnosis* / Q000209:etiology / Q000235:genetics; D006130:Growth Disorders / Q000150:complications / Q000175:diagnosis* / Q000235:genetics; D006319:Hearing Loss, Sensorineural / Q000150:complications / Q000175:diagnosis* / Q000235:genetics; D006801:Humans; D007037:Hypothyroidism / Q000150:complications / Q000175:diagnosis / Q000235:genetics; D008607:Intellectual Disability / Q000150:complications / Q000175:diagnosis / Q000235:genetics; D008297:Male; D009666:Nose / Q000002:abnormalities; D010182:Pancreatic Diseases / Q000150:complications / Q000175:diagnosis* / Q000235:genetics; D010641:Phenotype; D013577:Syndrome