국내 제2형 신경섬유종증 환자의 유전자 돌연변이와 임상증상 분석

Abstract

Background and Objectives Neurofibromatosis type 2 (NF2) is a rare autosomal dominantdisorder characterized as bilateral vestibular schwannoma (VS), various brain and spinal tumors. This study is aimed to investigate the relationship between the genotypes and phenotypesof NF2 found in the Korean population. Subjects and Method We retrospectively reviewed 11 patients who were diagnosed withNF2 and observed them for more than a year. NF2 gene mutations were detected using Sangersequencing and multiplex ligation-dependent probe amplification (MLPA). The mutationswere classified into tissue mosaicism, classic, and severe genotypes according to the UK NF2genetic severity score. Tumor load was assessed by reviewing MR images and audiologicalfindings were analyzed. Results We identified 7 cases (63.6%) of mutations from 11 patients who were diagnosedwith NF2. While three patients showed classic and four showed severe genotypes, four patientswere presumed as tissue mosaicism. The patients with severe genotypes didn’t show more severeclinical manifestations in terms of tumor load and hearing. Four patients with tissue mosaicismwere detected in the older age group than those with mutation. Of the five patients whohad serviceable bilateral hearing at the initial diagnosis, all maintained their serviceable hearingduring the follow-up. Conclusion Our results, which showed that the clinical manifestations of NF2 found in theKorean population have no correlation with the genotype findings, are not in agreement withprevious studies. However, further studies with larger sample sizes are needed to give moreappropriate counsel.