Mutation spectrum of the OPA1 gene in a large cohort of patients with suspected dominant optic atrophy: Identification and classification of 48 novel variants.

Autosomal dominant optic atrophy is one of the most common inherited optic neuropathies. This disease is genetically heterogeneous, but most cases are due to pathogenic variants in the OPA1 gene: depending on the population studied, 32-90% of cases harbor pathogenic variants in this gene. The aim of...

Full description

Bibliographic Details
Main Authors: Nicole Weisschuh, Simone Schimpf-Linzenbold, Pascale Mazzola, Sinja Kieninger, Ting Xiao, Ulrich Kellner, Teresa Neuhann, Carina Kelbsch, Felix Tonagel, Helmut Wilhelm, Susanne Kohl, Bernd Wissinger
Format: Article
Language:English
Published: Public Library of Science (PLoS) 2021-01-01
Series:PLoS ONE
Online Access:https://doi.org/10.1371/journal.pone.0253987
_version_ 1818404378614169600
author Nicole Weisschuh
Simone Schimpf-Linzenbold
Pascale Mazzola
Sinja Kieninger
Ting Xiao
Ulrich Kellner
Teresa Neuhann
Carina Kelbsch
Felix Tonagel
Helmut Wilhelm
Susanne Kohl
Bernd Wissinger
author_facet Nicole Weisschuh
Simone Schimpf-Linzenbold
Pascale Mazzola
Sinja Kieninger
Ting Xiao
Ulrich Kellner
Teresa Neuhann
Carina Kelbsch
Felix Tonagel
Helmut Wilhelm
Susanne Kohl
Bernd Wissinger
author_sort Nicole Weisschuh
collection DOAJ
description Autosomal dominant optic atrophy is one of the most common inherited optic neuropathies. This disease is genetically heterogeneous, but most cases are due to pathogenic variants in the OPA1 gene: depending on the population studied, 32-90% of cases harbor pathogenic variants in this gene. The aim of this study was to provide a comprehensive overview of the entire spectrum of likely pathogenic variants in the OPA1 gene in a large cohort of patients. Over a period of 20 years, 755 unrelated probands with a diagnosis of bilateral optic atrophy were referred to our laboratory for molecular genetic investigation. Genetic testing of the OPA1 gene was initially performed by a combined analysis using either single-strand conformation polymorphism or denaturing high performance liquid chromatography followed by Sanger sequencing to validate aberrant bands or melting profiles. The presence of copy number variations was assessed using multiplex ligation-dependent probe amplification. Since 2012, genetic testing was based on next-generation sequencing platforms. Genetic screening of the OPA1 gene revealed putatively pathogenic variants in 278 unrelated probands which represent 36.8% of the entire cohort. A total of 156 unique variants were identified, 78% of which can be considered null alleles. Variant c.2708_2711del/p.(V903Gfs*3) was found to constitute 14% of all disease-causing alleles. Special emphasis was placed on the validation of splice variants either by analyzing cDNA derived from patients´ blood samples or by heterologous splice assays using minigenes. Splicing analysis revealed different aberrant splicing events, including exon skipping, activation of exonic or intronic cryptic splice sites, and the inclusion of pseudoexons. Forty-eight variants that we identified were novel. Nine of them were classified as pathogenic, 34 as likely pathogenic and five as variant of uncertain significance. Our study adds a significant number of novel variants to the mutation spectrum of the OPA1 gene and will thereby facilitate genetic diagnostics of patients with suspected dominant optic atrophy.
first_indexed 2024-12-14T08:39:12Z
format Article
id doaj.art-79851959e93d45caa1af4f3bf738b073
institution Directory Open Access Journal
issn 1932-6203
language English
last_indexed 2024-12-14T08:39:12Z
publishDate 2021-01-01
publisher Public Library of Science (PLoS)
record_format Article
series PLoS ONE
spelling doaj.art-79851959e93d45caa1af4f3bf738b0732022-12-21T23:09:20ZengPublic Library of Science (PLoS)PLoS ONE1932-62032021-01-01167e025398710.1371/journal.pone.0253987Mutation spectrum of the OPA1 gene in a large cohort of patients with suspected dominant optic atrophy: Identification and classification of 48 novel variants.Nicole WeisschuhSimone Schimpf-LinzenboldPascale MazzolaSinja KieningerTing XiaoUlrich KellnerTeresa NeuhannCarina KelbschFelix TonagelHelmut WilhelmSusanne KohlBernd WissingerAutosomal dominant optic atrophy is one of the most common inherited optic neuropathies. This disease is genetically heterogeneous, but most cases are due to pathogenic variants in the OPA1 gene: depending on the population studied, 32-90% of cases harbor pathogenic variants in this gene. The aim of this study was to provide a comprehensive overview of the entire spectrum of likely pathogenic variants in the OPA1 gene in a large cohort of patients. Over a period of 20 years, 755 unrelated probands with a diagnosis of bilateral optic atrophy were referred to our laboratory for molecular genetic investigation. Genetic testing of the OPA1 gene was initially performed by a combined analysis using either single-strand conformation polymorphism or denaturing high performance liquid chromatography followed by Sanger sequencing to validate aberrant bands or melting profiles. The presence of copy number variations was assessed using multiplex ligation-dependent probe amplification. Since 2012, genetic testing was based on next-generation sequencing platforms. Genetic screening of the OPA1 gene revealed putatively pathogenic variants in 278 unrelated probands which represent 36.8% of the entire cohort. A total of 156 unique variants were identified, 78% of which can be considered null alleles. Variant c.2708_2711del/p.(V903Gfs*3) was found to constitute 14% of all disease-causing alleles. Special emphasis was placed on the validation of splice variants either by analyzing cDNA derived from patients´ blood samples or by heterologous splice assays using minigenes. Splicing analysis revealed different aberrant splicing events, including exon skipping, activation of exonic or intronic cryptic splice sites, and the inclusion of pseudoexons. Forty-eight variants that we identified were novel. Nine of them were classified as pathogenic, 34 as likely pathogenic and five as variant of uncertain significance. Our study adds a significant number of novel variants to the mutation spectrum of the OPA1 gene and will thereby facilitate genetic diagnostics of patients with suspected dominant optic atrophy.https://doi.org/10.1371/journal.pone.0253987
spellingShingle Nicole Weisschuh
Simone Schimpf-Linzenbold
Pascale Mazzola
Sinja Kieninger
Ting Xiao
Ulrich Kellner
Teresa Neuhann
Carina Kelbsch
Felix Tonagel
Helmut Wilhelm
Susanne Kohl
Bernd Wissinger
Mutation spectrum of the OPA1 gene in a large cohort of patients with suspected dominant optic atrophy: Identification and classification of 48 novel variants.
PLoS ONE
title Mutation spectrum of the OPA1 gene in a large cohort of patients with suspected dominant optic atrophy: Identification and classification of 48 novel variants.
title_full Mutation spectrum of the OPA1 gene in a large cohort of patients with suspected dominant optic atrophy: Identification and classification of 48 novel variants.
title_fullStr Mutation spectrum of the OPA1 gene in a large cohort of patients with suspected dominant optic atrophy: Identification and classification of 48 novel variants.
title_full_unstemmed Mutation spectrum of the OPA1 gene in a large cohort of patients with suspected dominant optic atrophy: Identification and classification of 48 novel variants.
title_short Mutation spectrum of the OPA1 gene in a large cohort of patients with suspected dominant optic atrophy: Identification and classification of 48 novel variants.
title_sort mutation spectrum of the opa1 gene in a large cohort of patients with suspected dominant optic atrophy identification and classification of 48 novel variants
url https://doi.org/10.1371/journal.pone.0253987
work_keys_str_mv AT nicoleweisschuh mutationspectrumoftheopa1geneinalargecohortofpatientswithsuspecteddominantopticatrophyidentificationandclassificationof48novelvariants
AT simoneschimpflinzenbold mutationspectrumoftheopa1geneinalargecohortofpatientswithsuspecteddominantopticatrophyidentificationandclassificationof48novelvariants
AT pascalemazzola mutationspectrumoftheopa1geneinalargecohortofpatientswithsuspecteddominantopticatrophyidentificationandclassificationof48novelvariants
AT sinjakieninger mutationspectrumoftheopa1geneinalargecohortofpatientswithsuspecteddominantopticatrophyidentificationandclassificationof48novelvariants
AT tingxiao mutationspectrumoftheopa1geneinalargecohortofpatientswithsuspecteddominantopticatrophyidentificationandclassificationof48novelvariants
AT ulrichkellner mutationspectrumoftheopa1geneinalargecohortofpatientswithsuspecteddominantopticatrophyidentificationandclassificationof48novelvariants
AT teresaneuhann mutationspectrumoftheopa1geneinalargecohortofpatientswithsuspecteddominantopticatrophyidentificationandclassificationof48novelvariants
AT carinakelbsch mutationspectrumoftheopa1geneinalargecohortofpatientswithsuspecteddominantopticatrophyidentificationandclassificationof48novelvariants
AT felixtonagel mutationspectrumoftheopa1geneinalargecohortofpatientswithsuspecteddominantopticatrophyidentificationandclassificationof48novelvariants
AT helmutwilhelm mutationspectrumoftheopa1geneinalargecohortofpatientswithsuspecteddominantopticatrophyidentificationandclassificationof48novelvariants
AT susannekohl mutationspectrumoftheopa1geneinalargecohortofpatientswithsuspecteddominantopticatrophyidentificationandclassificationof48novelvariants
AT berndwissinger mutationspectrumoftheopa1geneinalargecohortofpatientswithsuspecteddominantopticatrophyidentificationandclassificationof48novelvariants