J Korean Med Sci.  2006 Feb;21(1):107-112. 10.3346/jkms.2006.21.1.107.

The Spectrum of NF1 Mutations in Korean Patients with Neurofibromatosis Type 1

• Jeong SY
• Park SJ
• Kim HJ

• KMID: 2157792
• DOI: http://doi.org/10.3346/jkms.2006.21.1.107

Abstract

Neurofibromatosis type 1 (NF1) is one of the most common autosomal dominant disorders in humans. NF1 is caused by mutations in the NF1 gene which consists of 57 exons and encodes a GTPase activating protein (GAP), neurofibromin. To date, more than 640 different NF1 mutations have been identified and registered in the Human Gene Mutation Database (HGMD). In order to assess the NF1 mutational spectrum in Korean NF1 patients, we screened 23 unrelated Korean NF1 patients for mutations in the coding region and splice sites of the NF1 gene. We have identified 21 distinct NF1 mutations in 22 patients. The mutations included 10 single base substitutions (3 missense and 7 nonsense), 10 splice site mutations, and 1 single base deletion. Eight mutations have been previously identified and thirteen mutations were novel. The mutations are evenly distributed across exon 3 through intron 47 of the NF1 gene and no mutational hot spots were found. This analysis revealed a wide spectrum of NF1 mutations in Korean patients. A genotype- phenotype correlation analysis suggests that there is no clear relationship between specific NF1 mutations and clinical features of the disease.

Keyword

Neurofibromatosis 1; NF1 Gene; Mutation; Genotype; Phenotype; Variation; Korea

MeSH Terms

Adolescent
Adult
Child
Child, Preschool
DNA/chemistry/genetics
DNA Mutational Analysis
Genotype
Humans
Infant
Korea
Middle Aged
*Mutation
Neurofibromatosis 1/*genetics/pathology
Neurofibromin 1/*genetics
Phenotype
Research Support, Non-U.S. Gov't

Figure

• 

  Fig. 1 Location of the NF1 gene mutations detected in 22 unrelated Korean NF1 patients. The cAMP protein kinase recognition sites (cAMP/PK) spanning exons 11-17 and the GAP related domain (GRD) region spanning exons 20-27 are highlighted.

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