Two novel mutations in exons 19a and 20 and a BsaBI [correction of BsaI] polymorphism in a newly characterized intron of the neurofibromatosis type 1 gene

Hum Genet. 1998 Mar;102(3):367-71. doi: 10.1007/s004390050706.


Neurofibromatosis type 1 (NF1) is a common autosomal dominant disorder. It is caused by mutations in the NF1 gene, which comprises 60 exons and is located on chromosome 17q11.2. A total of 170 unrelated NF1 patients were screened for mutations in four exons by temperature-gradient gel electrophoresis. Preparatory work revealed the presence of a previously uncharacterized intron (19a) in what was previously designated exon 19; this allowed us to develop assays for genomic mutation screening in the newly defined exons 19a and 19b. Two novel NF1 mutations were detected: a single-base insertion in exon 19a creating a frameshift, and a second mutation affecting the splice donor site of intron 20 and leading to skipping of exon 20. A novel BsaBI polymorphism was identified in intron 19a.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Child
  • DNA Mutational Analysis / methods
  • Deoxyribonucleases, Type II Site-Specific
  • Electrophoresis, Polyacrylamide Gel / methods
  • Exons / genetics
  • Frameshift Mutation / genetics*
  • Genes, Neurofibromatosis 1 / genetics*
  • Genes, Neurofibromatosis 2 / genetics
  • Genetic Testing / methods
  • Humans
  • Introns / genetics
  • Male
  • Neurofibromatosis 1 / genetics*
  • Point Mutation / genetics*
  • Polymorphism, Restriction Fragment Length*


  • endodeoxyribonuclease BsaBI
  • Deoxyribonucleases, Type II Site-Specific