Molecular Diagnostics of NF1 in Slovakia Using cDNA and MLPA Analysis


Authors: M. Némethová 1,2;  A. Bolčeková 3;  S. Požgayová 2;  D. Ilenčíková 3;  A. Hlavatá 3;  Ľ. Kádaši 1,4;  L. Kovácz 3;  A. Zaťková 1
Authors‘ workplace: Laboratórium genetiky, ÚMFG SAV, Bratislava 1;  Laboratórium klinickej a molekulárnej genetiky, II. detská klinika LF UK a DFNsP Bratislava 2;  II. detská klinika LF UK a DFNsP Bratislava 3;  Katedra molekulárnej biológie, PriF UK, Bratislava 4
Published in: Cesk Slov Neurol N 2014; 77/110(6): 721-733
Category: Original Paper

Overview

Aim:
The aim of our study was to identify causative germline mutation in suspected NF1 patients, in order to help differential diagnostics, as well as to collect as large as possible group of patients for a possible genotype-phenotype correlations.

Material and methods:
Our set of patients consisted of 107 Slovak patients, recruited between 2008 and 2013, who were considered for a diagnosis NF1 by clinical genetics. In order to identify mutations, we employed NF1 cDNA sequencing that enabled us to also detect splicing mutations, as well as MLPA analysis that enables identification of larger deletions.

Results:
By employing the selected methods in our set of 94 unrelated Slovak patients who fulfilled the basic NF1 diagnostic criteria, we uncovered germline mutations in the NF1gene in 83 of them (88.3%). We observed a high proportion of mutations identified in Slovak population only so far (41/83, 49.4%), and we confirmed de novo mutation in 27/42 tested families (64.3%). Genotype-phenotype correlations revealed an increased incidence of optic pathway glioma in patients with a mutation in the 5´end of the NF1 gene.

Conclusion:
Combination of cDNA analysis and MLPA provides an effective method for identification of mutations in the NF1 gene. By employing these methods, we were able to also identify frequently incorrectly classified atypical splicing mutations. Clinical geneticists used our results in the differential diagnosis of the disease, especially in contested cases.

Key words:
NF1 gene – causative germline mutation – RNA splicing – genotype-phenotype correlation – de novo mutations –differential diagnostics

The authors declare they have no potential conflicts of interest concerning drugs, products, or services used in the study.

The Editorial Board declares that the manuscript met the ICMJE “uniform requirements” for biomedical papers.


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Paediatric neurology Neurosurgery Neurology

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Czech and Slovak Neurology and Neurosurgery

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