Jagged1 (JAG1) mutations in Alagille syndrome: increasing the mutation detection rate

Hum Mutat. 2006 May;27(5):436-43. doi: 10.1002/humu.20310.


Alagille syndrome (AGS) is caused by heterozygous mutations in JAG1, and mutations have been previously reported in about 70% of patients who meet clinical diagnostic criteria. We studied a cohort of 247 clinically well-defined patients, and using an aggressive and sequential screening approach we identified JAG1 mutations in 94% of individuals. Mutations were found in 232 out of 247 patients studied and 83 of the mutations were novel. This increase in the mutation rate was accomplished by combining rigorous clinical phenotyping, with a combination of mutation detection techniques, including fluorescence in situ hybridization (FISH), genomic and cDNA sequencing, and quantitative PCR. This higher rate of mutation identification has implications for clinical practice, facilitating genetic counseling, prenatal diagnosis, and evaluation of living-related liver transplant donors. Our results suggest that more aggressive screening may similarly increase the rate of mutation detection in other dominant and recessive disorders.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alagille Syndrome / diagnosis
  • Alagille Syndrome / genetics*
  • Calcium-Binding Proteins / genetics*
  • Cohort Studies
  • DNA Mutational Analysis
  • Genetic Testing
  • Humans
  • In Situ Hybridization, Fluorescence
  • Intercellular Signaling Peptides and Proteins
  • Jagged-1 Protein
  • Membrane Proteins / genetics*
  • Mutation*
  • Polymorphism, Genetic
  • Serrate-Jagged Proteins


  • Calcium-Binding Proteins
  • Intercellular Signaling Peptides and Proteins
  • JAG1 protein, human
  • Jagged-1 Protein
  • Membrane Proteins
  • Serrate-Jagged Proteins

Associated data

  • OMIM/118450
  • OMIM/601920