Next Generation Sequencing Identified a Novel Multi Exon Deletion of the Gene in a Chinese Pedigree with Neurofibromatosis Type 1

Neurofibromatosis type 1 (NF1) is a genetic disease involving neurocutaneous abnormalities. Neurofibromatosis type 1 is an autosomal dominant disorder characterized by the neurofibromas and café-au-lait spots. Mutation in the gene causes NF1. The gene encodes neurofibromin. In this study, we found a 31-year-old Chinese boy with NF1. He presented only with café-au-lait spots over the whole body. The proband's mother had a severe phenotype with neurofibroma and café-au-lait macules over her whole body, mostly in the facial region. A novel multi exon deletion c.(4661+1_4662-1)_(5748+1_5749-1)del; [EX36_39DEL] on the gene has been identified in the proband. Quantitative real-time polymerase chain reaction (qPCR) confirmed that this mutation is co-segregated well and was inherited from the proband's mother. The mutation was absent in the proband's father and normal individuals. The novel multi exon deletion results in the formation of a truncated NF1 protein that caused the NF1 phenotype in this family. Our present study also emphasized the significance of rapid, accurate and cost-effective screening for the patient with NF1 by next generation sequencing (NGS).