Childhood-onset Refractory Hypertension Results from Neurofibromatosis type 1 Caused by a Splicing NF1 mutation.

Abstract

BACKGROUND:

Neurofibromatosis type 1 (NF-1) is caused by mutations in the NF1 gene that encodes neurofibromin, a negative regulator of RAS proto-oncogene. Approximately one-third of the reported pathogenic mutations in NF1 are splicing mutations, but most consequences are unclear. The objective of this study was to identify the pathogenicity of splicing mutation in a Chinese family with NF-1 and determine the effects of the pre-mRNA splicing mutation by in vitro functional analysis.

METHODS:

Next-generation sequencing was used to screen candidate mutations. We performed a minigene splicing assay to determine the effect of the splicing mutation on NF1 expression and three-dimensional structure models of neurofibromin were generated using SWISS-MODEL and PROCHECK method, respectively.

RESULTS:

A pathogenic splicing mutation c.479+1G>C in NF1 was found in the proband characterized by childhood-onset refractory hypertension. In vitro analysis demonstrated that c.479+1G>C mutation caused skipping of exon 4, leading to a Glutamine to Valine substitution at position 97 in neurofibromin and an open reading frame shift terminating at codon 108. Protein modelling showed that several major domains were missing in the truncated neurofibromin protein.

CONCLUSION:

The splicing mutation c.479+1G>C identified in a Chinese patient with NF-1 and childhood-onset refractory hypertension caused skipping of exon 4 and a truncated protein. Our findings offered new evidence for the molecular diagnosis of NF-1.

• Authors: Yi-Ting Lu, Buweimairemu Rejiepu, Di Zhang, Dong-Cheng Cai, Kun-Qi Yang, Tao Tian, Xian-Liang Zhou, Peng Fan
• Journal: Kidney & blood pressure research (Kidney Blood Press Res) (Aug 10 2023) ISSN: 1423-0143 [Electronic] Switzerland
• PMID: 37562365 (Publication Type: Journal Article)
• Copyright: The Author(s). Published by S. Karger AG, Basel.