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Elshwekh H, Alhudiri IM, Elzagheid A, Enattah N, Abbassi Y, Abou Assali L, Marino I, Stuani C, Buratti E, Romano M. Assessing the Impact of Novel BRCA1 Exon 11 Variants on Pre-mRNA Splicing. Cells 2024; 13:824. [PMID: 38786046 PMCID: PMC11119505 DOI: 10.3390/cells13100824] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2024] [Revised: 05/06/2024] [Accepted: 05/09/2024] [Indexed: 05/25/2024] Open
Abstract
Our study focused on assessing the effects of three newly identified BRCA1 exon 11 variants (c.1019T>C, c.2363T>G, and c.3192T>C) on breast cancer susceptibility. Using computational predictions and experimental splicing assays, we evaluated their potential as pathogenic mutations. Our in silico analyses suggested that the c.2363T>G and c.3192T>C variants could impact both splicing and protein function, resulting in the V340A and V788G mutations, respectively. We further examined their splicing effects using minigene assays in MCF7 and SKBR3 breast cancer cell lines. Interestingly, we found that the c.2363T>G variant significantly altered splicing patterns in MCF7 cells but not in SKBR3 cells. This finding suggests a potential influence of cellular context on the variant's effects. While attempts to correlate in silico predictions with RNA binding factors were inconclusive, this observation underscores the complexity of splicing regulation. Splicing is governed by various factors, including cellular contexts and protein interactions, making it challenging to predict outcomes accurately. Further research is needed to fully understand the functional consequences of the c.2363T>G variant in breast cancer pathogenesis. Integrating computational predictions with experimental data will provide valuable insights into the role of alternative splicing regulation in different breast cancer types and stages.
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Affiliation(s)
- Halla Elshwekh
- International Centre for Genetic Engineering and Biotechnology, Padriciano 99, 34149 Trieste, Italy; (H.E.); (Y.A.); (L.A.A.); (I.M.); (C.S.)
- Department of Genetic Engineering, Libyan Biotechnology Research Center, Tripoli P.O. Box 30313, Libya; (I.M.A.); (A.E.); (N.E.)
| | - Inas M. Alhudiri
- Department of Genetic Engineering, Libyan Biotechnology Research Center, Tripoli P.O. Box 30313, Libya; (I.M.A.); (A.E.); (N.E.)
| | - Adam Elzagheid
- Department of Genetic Engineering, Libyan Biotechnology Research Center, Tripoli P.O. Box 30313, Libya; (I.M.A.); (A.E.); (N.E.)
| | - Nabil Enattah
- Department of Genetic Engineering, Libyan Biotechnology Research Center, Tripoli P.O. Box 30313, Libya; (I.M.A.); (A.E.); (N.E.)
| | - Yasmine Abbassi
- International Centre for Genetic Engineering and Biotechnology, Padriciano 99, 34149 Trieste, Italy; (H.E.); (Y.A.); (L.A.A.); (I.M.); (C.S.)
| | - Lubna Abou Assali
- International Centre for Genetic Engineering and Biotechnology, Padriciano 99, 34149 Trieste, Italy; (H.E.); (Y.A.); (L.A.A.); (I.M.); (C.S.)
| | - Ilenia Marino
- International Centre for Genetic Engineering and Biotechnology, Padriciano 99, 34149 Trieste, Italy; (H.E.); (Y.A.); (L.A.A.); (I.M.); (C.S.)
- Faculty of Medicine, University of Southampton, Southampton SO17 1BJ, UK
| | - Cristiana Stuani
- International Centre for Genetic Engineering and Biotechnology, Padriciano 99, 34149 Trieste, Italy; (H.E.); (Y.A.); (L.A.A.); (I.M.); (C.S.)
| | - Emanuele Buratti
- International Centre for Genetic Engineering and Biotechnology, Padriciano 99, 34149 Trieste, Italy; (H.E.); (Y.A.); (L.A.A.); (I.M.); (C.S.)
| | - Maurizio Romano
- Department of Life Sciences, University of Trieste, Via A. Valerio, 28, 34127 Trieste, Italy
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Holm LL, Doktor TK, Flugt KK, Petersen US, Petersen R, Andresen B. All exons are not created equal-exon vulnerability determines the effect of exonic mutations on splicing. Nucleic Acids Res 2024; 52:4588-4603. [PMID: 38324470 PMCID: PMC11077056 DOI: 10.1093/nar/gkae077] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2023] [Revised: 01/05/2024] [Accepted: 01/26/2024] [Indexed: 02/09/2024] Open
Abstract
It is now widely accepted that aberrant splicing of constitutive exons is often caused by mutations affecting cis-acting splicing regulatory elements (SREs), but there is a misconception that all exons have an equal dependency on SREs and thus a similar vulnerability to aberrant splicing. We demonstrate that some exons are more likely to be affected by exonic splicing mutations (ESMs) due to an inherent vulnerability, which is context dependent and influenced by the strength of exon definition. We have developed VulExMap, a tool which is based on empirical data that can designate whether a constitutive exon is vulnerable. Using VulExMap, we find that only 25% of all exons can be categorized as vulnerable, whereas two-thirds of 359 previously reported ESMs in 75 disease genes are located in vulnerable exons. Because VulExMap analysis is based on empirical data on splicing of exons in their endogenous context, it includes all features important in determining the vulnerability. We believe that VulExMap will be an important tool when assessing the effect of exonic mutations by pinpointing whether they are located in exons vulnerable to ESMs.
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Affiliation(s)
- Lise L Holm
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, 5230 Odense M, Denmark
- Villum Center for Bioanalytical Sciences, University of Southern Denmark, 5230 Odense M, Denmark
| | - Thomas K Doktor
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, 5230 Odense M, Denmark
- Villum Center for Bioanalytical Sciences, University of Southern Denmark, 5230 Odense M, Denmark
| | - Katharina K Flugt
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, 5230 Odense M, Denmark
- Villum Center for Bioanalytical Sciences, University of Southern Denmark, 5230 Odense M, Denmark
| | - Ulrika S S Petersen
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, 5230 Odense M, Denmark
- Villum Center for Bioanalytical Sciences, University of Southern Denmark, 5230 Odense M, Denmark
| | - Rikke Petersen
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, 5230 Odense M, Denmark
- Villum Center for Bioanalytical Sciences, University of Southern Denmark, 5230 Odense M, Denmark
| | - Brage S Andresen
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, 5230 Odense M, Denmark
- Villum Center for Bioanalytical Sciences, University of Southern Denmark, 5230 Odense M, Denmark
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Sanoguera-Miralles L, Llinares-Burguet I, Bueno-Martínez E, Ramadane-Morchadi L, Stuani C, Valenzuela-Palomo A, García-Álvarez A, Pérez-Segura P, Buratti E, de la Hoya M, Velasco-Sampedro EA. Comprehensive splicing analysis of the alternatively spliced CHEK2 exons 8 and 10 reveals three enhancer/silencer-rich regions and 38 spliceogenic variants. J Pathol 2024; 262:395-409. [PMID: 38332730 DOI: 10.1002/path.6243] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Revised: 10/26/2023] [Accepted: 11/28/2023] [Indexed: 02/10/2024]
Abstract
Splicing is controlled by a large set of regulatory elements (SREs) including splicing enhancers and silencers, which are involved in exon recognition. Variants at these motifs may dysregulate splicing and trigger loss-of-function transcripts associated with disease. Our goal here was to study the alternatively spliced exons 8 and 10 of the breast cancer susceptibility gene CHEK2. For this purpose, we used a previously published minigene with exons 6-10 that produced the expected minigene full-length transcript and replicated the naturally occurring events of exon 8 [Δ(E8)] and exon 10 [Δ(E10)] skipping. We then introduced 12 internal microdeletions of exons 8 and 10 by mutagenesis in order to map SRE-rich intervals by splicing assays in MCF-7 cells. We identified three minimal (10-, 11-, 15-nt) regions essential for exon recognition: c.863_877del [ex8, Δ(E8): 75%] and c.1073_1083del and c.1083_1092del [ex10, Δ(E10): 97% and 62%, respectively]. Then 87 variants found within these intervals were introduced into the wild-type minigene and tested functionally. Thirty-eight of them (44%) impaired splicing, four of which (c.883G>A, c.883G>T, c.884A>T, and c.1080G>T) induced negligible amounts (<5%) of the minigene full-length transcript. Another six variants (c.886G>A, c.886G>T, c.1075G>A, c.1075G>T, c.1076A>T, and c.1078G>T) showed significantly strong impacts (20-50% of the minigene full-length transcript). Thirty-three of the 38 spliceogenic variants were annotated as missense, three as nonsense, and two as synonymous, underlying the fact that any exonic change is capable of disrupting splicing. Moreover, c.883G>A, c.883G>T, and c.884A>T were classified as pathogenic/likely pathogenic variants according to ACMG/AMP (American College of Medical Genetics and Genomics/Association for Molecular Pathology)-based criteria. © 2024 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.
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Affiliation(s)
- Lara Sanoguera-Miralles
- Splicing and Genetic Susceptibility to Cancer, Unidad de Excelencia Instituto de Biomedicina y Genética Molecular de Valladolid (IBGM), Consejo Superior de Investigaciones Científicas - Universidad de Valladolid (CSIC-UVa), Valladolid, Spain
| | - Inés Llinares-Burguet
- Splicing and Genetic Susceptibility to Cancer, Unidad de Excelencia Instituto de Biomedicina y Genética Molecular de Valladolid (IBGM), Consejo Superior de Investigaciones Científicas - Universidad de Valladolid (CSIC-UVa), Valladolid, Spain
| | - Elena Bueno-Martínez
- Splicing and Genetic Susceptibility to Cancer, Unidad de Excelencia Instituto de Biomedicina y Genética Molecular de Valladolid (IBGM), Consejo Superior de Investigaciones Científicas - Universidad de Valladolid (CSIC-UVa), Valladolid, Spain
| | - Lobna Ramadane-Morchadi
- Molecular Oncology Laboratory CIBERONC, Hospital Clínico San Carlos, IdISSC (Instituto de Investigación Sanitaria del Hospital Clínico San Carlos), Madrid, Spain
| | - Cristiana Stuani
- Molecular Pathology Lab. International Centre of Genetic Engineering and Biotechnology, Trieste, Italy
| | - Alberto Valenzuela-Palomo
- Splicing and Genetic Susceptibility to Cancer, Unidad de Excelencia Instituto de Biomedicina y Genética Molecular de Valladolid (IBGM), Consejo Superior de Investigaciones Científicas - Universidad de Valladolid (CSIC-UVa), Valladolid, Spain
| | - Alicia García-Álvarez
- Splicing and Genetic Susceptibility to Cancer, Unidad de Excelencia Instituto de Biomedicina y Genética Molecular de Valladolid (IBGM), Consejo Superior de Investigaciones Científicas - Universidad de Valladolid (CSIC-UVa), Valladolid, Spain
| | - Pedro Pérez-Segura
- Molecular Oncology Laboratory CIBERONC, Hospital Clínico San Carlos, IdISSC (Instituto de Investigación Sanitaria del Hospital Clínico San Carlos), Madrid, Spain
| | - Emanuele Buratti
- Molecular Pathology Lab. International Centre of Genetic Engineering and Biotechnology, Trieste, Italy
| | - Miguel de la Hoya
- Molecular Oncology Laboratory CIBERONC, Hospital Clínico San Carlos, IdISSC (Instituto de Investigación Sanitaria del Hospital Clínico San Carlos), Madrid, Spain
| | - Eladio A Velasco-Sampedro
- Splicing and Genetic Susceptibility to Cancer, Unidad de Excelencia Instituto de Biomedicina y Genética Molecular de Valladolid (IBGM), Consejo Superior de Investigaciones Científicas - Universidad de Valladolid (CSIC-UVa), Valladolid, Spain
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Zhang H, Xin M, Lin L, Chen C, Balestra D, Ding Q. Pleiotropic effects of different exonic nucleotide changes at the same position contribute to hemophilia B phenotypic variation. J Thromb Haemost 2024; 22:975-989. [PMID: 38184202 DOI: 10.1016/j.jtha.2023.12.031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2023] [Revised: 12/29/2023] [Accepted: 12/29/2023] [Indexed: 01/08/2024]
Abstract
BACKGROUND The disease-causing effects of genetic variations often depend on their location within a gene. Exonic changes generally lead to alterations in protein production, secretion, activity, or clearance. However, owing to the overlap between proteins and splicing codes, missense variants can also affect messenger RNA splicing, thus adding a layer of complexity and influencing disease phenotypes. OBJECTIVES To extensively characterize a panel of 13 exonic variants in the F9 gene occurring at 6 different factor IX positions and associated with varying severities of hemophilia B (HB). METHODS Computational predictions, splicing analysis, and recombinant factor IX assays were exploited to characterize F9 variants. RESULTS We demonstrated that 5 (38%) of 13 selected F9 exonic variants have pleiotropic effects. Although bioinformatic approaches accurately classified effects, extensive experimental assays were required to elucidate and deepen the molecular mechanisms underlying the pleiotropic effects. Importantly, their characterization was instrumental in developing tailored RNA therapeutics based on engineered U7 small nuclear RNA to mask cryptic splice sites and compensatory U1 small nuclear RNA to enhance exon definition. CONCLUSION Overall, albeit a multitool bioinformatic approach suggested the molecular effects of multiple HB variants, the deep investigation of molecular mechanisms revealed insights into the HB phenotype-genotype relationship, enabling accurate classification of HB variants. Importantly, knowledge of molecular mechanisms allowed the development of tailored RNA therapeutics, which can also be translated to other genetic diseases.
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Affiliation(s)
- Huayang Zhang
- Department of Laboratory Medicine, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China; State Key Laboratory of Medical Genomics, Shanghai Institute of Hematology, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Min Xin
- Department of Laboratory Medicine, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China; State Key Laboratory of Medical Genomics, Shanghai Institute of Hematology, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Liya Lin
- Department of Laboratory Medicine, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China; State Key Laboratory of Medical Genomics, Shanghai Institute of Hematology, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Changming Chen
- Department of Laboratory Medicine, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China; State Key Laboratory of Medical Genomics, Shanghai Institute of Hematology, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Dario Balestra
- Department of Life Sciences and Biotechnology, University of Ferrara, Ferrara, Italy.
| | - Qiulan Ding
- Department of Laboratory Medicine, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China; Collaborative Innovation Center of Hematology, Shanghai Jiaotong University School of Medicine, Shanghai, China.
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Spangsberg Petersen US, Dembic M, Martínez-Pizarro A, Richard E, Holm LL, Havelund JF, Doktor TK, Larsen MR, Færgeman NJ, Desviat LR, Andresen BS. Regulating PCCA gene expression by modulation of pseudoexon splicing patterns to rescue enzyme activity in propionic acidemia. MOLECULAR THERAPY. NUCLEIC ACIDS 2024; 35:102101. [PMID: 38204914 PMCID: PMC10776996 DOI: 10.1016/j.omtn.2023.102101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/10/2023] [Accepted: 12/08/2023] [Indexed: 01/12/2024]
Abstract
Pseudoexons are nonfunctional intronic sequences that can be activated by deep-intronic sequence variation. Activation increases pseudoexon inclusion in mRNA and interferes with normal gene expression. The PCCA c.1285-1416A>G variation activates a pseudoexon and causes the severe metabolic disorder propionic acidemia by deficiency of the propionyl-CoA carboxylase enzyme encoded by PCCA and PCCB. We characterized this pathogenic pseudoexon activation event in detail and identified hnRNP A1 to be important for normal repression. The PCCA c.1285-1416A>G variation disrupts an hnRNP A1-binding splicing silencer and simultaneously creates a splicing enhancer. We demonstrate that blocking this region of regulation with splice-switching antisense oligonucleotides restores normal splicing and rescues enzyme activity in patient fibroblasts and in a cellular model created by CRISPR gene editing. Interestingly, the PCCA pseudoexon offers an unexploited potential to upregulate gene expression because healthy tissues show relatively high inclusion levels. By blocking inclusion of the nonactivated wild-type pseudoexon, we can increase both PCCA and PCCB protein levels, which increases the activity of the heterododecameric enzyme. Surprisingly, we can increase enzyme activity from residual levels in not only patient fibroblasts harboring PCCA missense variants but also those harboring PCCB missense variants. This is a potential treatment strategy for propionic acidemia.
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Affiliation(s)
- Ulrika Simone Spangsberg Petersen
- Department of Biochemistry and Molecular Biology and the Villum Center for Bioanalytical Sciences, University of Southern Denmark, 5230 Odense M, Denmark
| | - Maja Dembic
- Department of Biochemistry and Molecular Biology and the Villum Center for Bioanalytical Sciences, University of Southern Denmark, 5230 Odense M, Denmark
- Department of Clinical Genetics, Odense University Hospital, 5000 Odense C, Denmark
- Department of Mathematics and Computer Science, University of Southern Denmark, 5230 Odense M, Denmark
| | - Ainhoa Martínez-Pizarro
- Centro de Biología Molecular Severo Ochoa, UAM-CSIC, CEDEM, CIBERER, IdiPaz, Universidad Autónoma de Madrid, 28049 Madrid, Spain
| | - Eva Richard
- Centro de Biología Molecular Severo Ochoa, UAM-CSIC, CEDEM, CIBERER, IdiPaz, Universidad Autónoma de Madrid, 28049 Madrid, Spain
| | - Lise Lolle Holm
- Department of Biochemistry and Molecular Biology and the Villum Center for Bioanalytical Sciences, University of Southern Denmark, 5230 Odense M, Denmark
| | - Jesper Foged Havelund
- Department of Biochemistry and Molecular Biology and the Villum Center for Bioanalytical Sciences, University of Southern Denmark, 5230 Odense M, Denmark
| | - Thomas Koed Doktor
- Department of Biochemistry and Molecular Biology and the Villum Center for Bioanalytical Sciences, University of Southern Denmark, 5230 Odense M, Denmark
| | - Martin Røssel Larsen
- Department of Biochemistry and Molecular Biology and the Villum Center for Bioanalytical Sciences, University of Southern Denmark, 5230 Odense M, Denmark
| | - Nils J. Færgeman
- Department of Biochemistry and Molecular Biology and the Villum Center for Bioanalytical Sciences, University of Southern Denmark, 5230 Odense M, Denmark
| | - Lourdes Ruiz Desviat
- Centro de Biología Molecular Severo Ochoa, UAM-CSIC, CEDEM, CIBERER, IdiPaz, Universidad Autónoma de Madrid, 28049 Madrid, Spain
| | - Brage Storstein Andresen
- Department of Biochemistry and Molecular Biology and the Villum Center for Bioanalytical Sciences, University of Southern Denmark, 5230 Odense M, Denmark
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Smith C, Kitzman JO. Benchmarking splice variant prediction algorithms using massively parallel splicing assays. Genome Biol 2023; 24:294. [PMID: 38129864 PMCID: PMC10734170 DOI: 10.1186/s13059-023-03144-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Accepted: 12/13/2023] [Indexed: 12/23/2023] Open
Abstract
BACKGROUND Variants that disrupt mRNA splicing account for a sizable fraction of the pathogenic burden in many genetic disorders, but identifying splice-disruptive variants (SDVs) beyond the essential splice site dinucleotides remains difficult. Computational predictors are often discordant, compounding the challenge of variant interpretation. Because they are primarily validated using clinical variant sets heavily biased to known canonical splice site mutations, it remains unclear how well their performance generalizes. RESULTS We benchmark eight widely used splicing effect prediction algorithms, leveraging massively parallel splicing assays (MPSAs) as a source of experimentally determined ground-truth. MPSAs simultaneously assay many variants to nominate candidate SDVs. We compare experimentally measured splicing outcomes with bioinformatic predictions for 3,616 variants in five genes. Algorithms' concordance with MPSA measurements, and with each other, is lower for exonic than intronic variants, underscoring the difficulty of identifying missense or synonymous SDVs. Deep learning-based predictors trained on gene model annotations achieve the best overall performance at distinguishing disruptive and neutral variants, and controlling for overall call rate genome-wide, SpliceAI and Pangolin have superior sensitivity. Finally, our results highlight two practical considerations when scoring variants genome-wide: finding an optimal score cutoff, and the substantial variability introduced by differences in gene model annotation, and we suggest strategies for optimal splice effect prediction in the face of these issues. CONCLUSION SpliceAI and Pangolin show the best overall performance among predictors tested, however, improvements in splice effect prediction are still needed especially within exons.
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Affiliation(s)
- Cathy Smith
- Department of Human Genetics, University of Michigan Medical School, Ann Arbor, MI, 48109, USA
- Department of Computational Medicine and Bioinformatics, University of Michigan Medical School, Ann Arbor, MI, 48109, USA
| | - Jacob O Kitzman
- Department of Human Genetics, University of Michigan Medical School, Ann Arbor, MI, 48109, USA.
- Department of Computational Medicine and Bioinformatics, University of Michigan Medical School, Ann Arbor, MI, 48109, USA.
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7
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Chograni M, Alahdal HM, Rejili M. Autosomal recessive congenital cataract is associated with a novel 4-bp splicing deletion mutation in a novel C10orf71 human gene. Hum Genomics 2023; 17:41. [PMID: 37179318 PMCID: PMC10182639 DOI: 10.1186/s40246-023-00492-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2023] [Accepted: 05/09/2023] [Indexed: 05/15/2023] Open
Abstract
Congenital cataract is one of the most genetically heterogeneous ocular conditions with different genes involved in its etiology. Here, we describe the analysis of a new candidate gene of a congenital bilateral cataract associated with polymalformative syndrome, moderate global developmental delay, microcephaly, axial hypotonia, intrauterine growth restriction and facial dysmorphism for two affected siblings. Molecular analysis included exome sequencing and genome wide homozygosity mapping revealed a region of homozygosity shared by the two affected siblings at 10q11.23. The new C10orf71 gene was included in this interval and direct sequencing of this gene revealed an already described homozygous c. 2123T > G mutation (p. L708R) for the two affected subjects. Interestingly, we revealed in contrast a 4-bp deletion on the 3'-splicing acceptor site of intron 3-exon 4, namely defined as IVS3-5delGCAA. The C10Orf71 gene expression analysis using RT-PCR showed an expression pattern in different fetal organs and tissues as well as in leukocytes and confirmed that the IVS3-5delGCAA deletion of the C10orf71 gene is a splicing mutation responsible for the shortening of the C10orf71 protein in the two related patients. The C10orf71 gene has not been described to date as associated to the autosomal recessive phenotype.
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Affiliation(s)
- M Chograni
- Faculté de Médecine de Tunis, Laboratoire Génétique Humaine, University Tunis El Manar, Tunis, Tunisia
| | - H M Alahdal
- Department of Biology, College of Science, Princess Nourah Bint Abdulrahman University, Riyadh, Saudi Arabia.
| | - M Rejili
- Department of Life Sciences, College of Sciences, Al Imam Mohammad Ibn Saud Islamic University (IMSIU), Riyadh, 11623, Saudi Arabia
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Smith C, Kitzman JO. Benchmarking splice variant prediction algorithms using massively parallel splicing assays. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.04.539398. [PMID: 37205456 PMCID: PMC10187268 DOI: 10.1101/2023.05.04.539398] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Background Variants that disrupt mRNA splicing account for a sizable fraction of the pathogenic burden in many genetic disorders, but identifying splice-disruptive variants (SDVs) beyond the essential splice site dinucleotides remains difficult. Computational predictors are often discordant, compounding the challenge of variant interpretation. Because they are primarily validated using clinical variant sets heavily biased to known canonical splice site mutations, it remains unclear how well their performance generalizes. Results We benchmarked eight widely used splicing effect prediction algorithms, leveraging massively parallel splicing assays (MPSAs) as a source of experimentally determined ground-truth. MPSAs simultaneously assay many variants to nominate candidate SDVs. We compared experimentally measured splicing outcomes with bioinformatic predictions for 3,616 variants in five genes. Algorithms' concordance with MPSA measurements, and with each other, was lower for exonic than intronic variants, underscoring the difficulty of identifying missense or synonymous SDVs. Deep learning-based predictors trained on gene model annotations achieved the best overall performance at distinguishing disruptive and neutral variants. Controlling for overall call rate genome-wide, SpliceAI and Pangolin also showed superior overall sensitivity for identifying SDVs. Finally, our results highlight two practical considerations when scoring variants genome-wide: finding an optimal score cutoff, and the substantial variability introduced by differences in gene model annotation, and we suggest strategies for optimal splice effect prediction in the face of these issues. Conclusion SpliceAI and Pangolin showed the best overall performance among predictors tested, however, improvements in splice effect prediction are still needed especially within exons.
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Affiliation(s)
- Cathy Smith
- Department of Human Genetics, University of Michigan Medical School, Ann Arbor, MI 48109, USA
- Department of Computational Medicine and Bioinformatics, University of Michigan Medical School, Ann Arbor, MI 48109, USA
| | - Jacob O. Kitzman
- Department of Human Genetics, University of Michigan Medical School, Ann Arbor, MI 48109, USA
- Department of Computational Medicine and Bioinformatics, University of Michigan Medical School, Ann Arbor, MI 48109, USA
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9
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Rogalska ME, Vivori C, Valcárcel J. Regulation of pre-mRNA splicing: roles in physiology and disease, and therapeutic prospects. Nat Rev Genet 2023; 24:251-269. [PMID: 36526860 DOI: 10.1038/s41576-022-00556-8] [Citation(s) in RCA: 20] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/10/2022] [Indexed: 12/23/2022]
Abstract
The removal of introns from mRNA precursors and its regulation by alternative splicing are key for eukaryotic gene expression and cellular function, as evidenced by the numerous pathologies induced or modified by splicing alterations. Major recent advances have been made in understanding the structures and functions of the splicing machinery, in the description and classification of physiological and pathological isoforms and in the development of the first therapies for genetic diseases based on modulation of splicing. Here, we review this progress and discuss important remaining challenges, including predicting splice sites from genomic sequences, understanding the variety of molecular mechanisms and logic of splicing regulation, and harnessing this knowledge for probing gene function and disease aetiology and for the design of novel therapeutic approaches.
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Affiliation(s)
- Malgorzata Ewa Rogalska
- Genome Biology Program, Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Claudia Vivori
- Genome Biology Program, Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Barcelona, Spain
- Department of Medicine and Life Sciences, Universitat Pompeu Fabra (UPF), Barcelona, Spain
- The Francis Crick Institute, London, UK
| | - Juan Valcárcel
- Genome Biology Program, Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Barcelona, Spain.
- Department of Medicine and Life Sciences, Universitat Pompeu Fabra (UPF), Barcelona, Spain.
- Institució Catalana de Recerca i Estudis Avançats (ICREA), Barcelona, Spain.
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Barbosa P, Savisaar R, Carmo-Fonseca M, Fonseca A. Computational prediction of human deep intronic variation. Gigascience 2022; 12:giad085. [PMID: 37878682 PMCID: PMC10599398 DOI: 10.1093/gigascience/giad085] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Revised: 06/07/2023] [Accepted: 09/20/2023] [Indexed: 10/27/2023] Open
Abstract
BACKGROUND The adoption of whole-genome sequencing in genetic screens has facilitated the detection of genetic variation in the intronic regions of genes, far from annotated splice sites. However, selecting an appropriate computational tool to discriminate functionally relevant genetic variants from those with no effect is challenging, particularly for deep intronic regions where independent benchmarks are scarce. RESULTS In this study, we have provided an overview of the computational methods available and the extent to which they can be used to analyze deep intronic variation. We leveraged diverse datasets to extensively evaluate tool performance across different intronic regions, distinguishing between variants that are expected to disrupt splicing through different molecular mechanisms. Notably, we compared the performance of SpliceAI, a widely used sequence-based deep learning model, with that of more recent methods that extend its original implementation. We observed considerable differences in tool performance depending on the region considered, with variants generating cryptic splice sites being better predicted than those that potentially affect splicing regulatory elements. Finally, we devised a novel quantitative assessment of tool interpretability and found that tools providing mechanistic explanations of their predictions are often correct with respect to the ground - information, but the use of these tools results in decreased predictive power when compared to black box methods. CONCLUSIONS Our findings translate into practical recommendations for tool usage and provide a reference framework for applying prediction tools in deep intronic regions, enabling more informed decision-making by practitioners.
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Affiliation(s)
- Pedro Barbosa
- LASIGE, Departamento de Informática, Faculdade de Ciências, Universidade de Lisboa, 1749-016,, Lisboa, Portugal
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, 1649-028, Lisboa, Portugal
| | | | - Maria Carmo-Fonseca
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, 1649-028, Lisboa, Portugal
| | - Alcides Fonseca
- LASIGE, Departamento de Informática, Faculdade de Ciências, Universidade de Lisboa, 1749-016,, Lisboa, Portugal
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11
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Rossi G, Salvi E, Mehmeti E, Ricci M, Villa C, Prioni S, Moda F, Di Fede G, Tiraboschi P, Redaelli V, Coppola C, Koch G, Canu E, Filippi M, Agosta F, Giaccone G, Caroppo P. Semantic and right temporal variant of FTD: Next generation sequencing genetic analysis on a single-center cohort. Front Aging Neurosci 2022; 14:1085406. [PMID: 36570531 PMCID: PMC9773257 DOI: 10.3389/fnagi.2022.1085406] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Accepted: 11/21/2022] [Indexed: 12/13/2022] Open
Abstract
Semantic and right temporal variant of frontotemporal dementia (svFTD and rtvFTD) are rare clinical phenotypes in which, in most cases, the underlying pathology is TDP-43 proteinopathy. They are usually sporadic disorders, but recent evidences suggest a higher frequency of genetic mutations for the right temporal versus the semantic variant. However, the genetic basis of these forms is not clear. In this study we performed a genetic screening of a single-center cohort of svFTD and rtvFTD patients, aiming at identifying the associated genetic variants. A panel of 73 dementia candidate genes has been analyzed by NGS target sequencing including both causal and risk/modifier genes in 23 patients (15 svFTD and 8 rtvFTD) and 73 healthy age-matched controls. We first performed a single variant analysis considering rare variants and then a gene-based aggregation analysis to evaluate the cumulative effects of multiple rare variants in a single gene. We found 12 variants in nearly 40% of patients (9/23), described as pathogenic or classified as VUS/likely pathogenic. The overall rate was higher in svFTD than in rtvFTD. Three mutations were located in MAPT gene and single mutations in the following genes: SQSTM1, VCP, PSEN1, TBK1, OPTN, CHCHD10, PRKN, DCTN1. Our study revealed the presence of variants in genes involved in pathways relevant for the pathology, especially autophagy and inflammation. We suggest that molecular analysis should be performed in all svFTD and rtvFTD patients, to better understand the genotype-phenotype correlation and the pathogenetic mechanisms that could drive the clinical phenotypes in FTD.
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Affiliation(s)
- Giacomina Rossi
- Neurology V and Neuropathology Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy,*Correspondence: Giacomina Rossi,
| | - Erika Salvi
- Neuroalgology Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Elkadia Mehmeti
- Neuroalgology Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Martina Ricci
- Neurology V and Neuropathology Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Cristina Villa
- Neurology V and Neuropathology Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Sara Prioni
- Clinical Neuropsychology Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Fabio Moda
- Neurology V and Neuropathology Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Giuseppe Di Fede
- Neurology V and Neuropathology Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Pietro Tiraboschi
- Neurology V and Neuropathology Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Veronica Redaelli
- Neurology V and Neuropathology Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Cinzia Coppola
- Department of Advanced Medical and Surgical Sciences, University of Campania “L. Vanvitelli”, Naples, Italy
| | - Giacomo Koch
- Non Invasive Brain Stimulation Unit/Department of Behavioral and Clinical Neurology, Santa Lucia Foundation IRCCS, Rome, Italy
| | - Elisa Canu
- Neuroimaging Research Unit, Division of Neuroscience, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - Massimo Filippi
- Neuroimaging Research Unit, Division of Neuroscience, IRCCS San Raffaele Scientific Institute, Milan, Italy,Neurology Unit, IRCCS San Raffaele Scientific Institute, Milan, Italy,Vita-Salute San Raffaele University, Milan, Italy,Unit of Neurorehabilitation, IRCCS San Raffaele Scientific Institute, Milan, Italy,Neurophysiology Service, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - Federica Agosta
- Neuroimaging Research Unit, Division of Neuroscience, IRCCS San Raffaele Scientific Institute, Milan, Italy,Neurology Unit, IRCCS San Raffaele Scientific Institute, Milan, Italy,Vita-Salute San Raffaele University, Milan, Italy
| | - Giorgio Giaccone
- Neurology V and Neuropathology Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Paola Caroppo
- Neurology V and Neuropathology Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
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12
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Leman R, Parfait B, Vidaud D, Girodon E, Pacot L, Le Gac G, Ka C, Ferec C, Fichou Y, Quesnelle C, Aucouturier C, Muller E, Vaur D, Castera L, Boulouard F, Ricou A, Tubeuf H, Soukarieh O, Gaildrat P, Riant F, Guillaud‐Bataille M, Caputo SM, Caux‐Moncoutier V, Boutry‐Kryza N, Bonnet‐Dorion F, Schultz I, Rossing M, Quenez O, Goldenberg L, Harter V, Parsons MT, Spurdle AB, Frébourg T, Martins A, Houdayer C, Krieger S. SPiP: Splicing Prediction Pipeline, a machine learning tool for massive detection of exonic and intronic variant effects on mRNA splicing. Hum Mutat 2022; 43:2308-2323. [PMID: 36273432 PMCID: PMC10946553 DOI: 10.1002/humu.24491] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2022] [Revised: 10/06/2022] [Accepted: 10/18/2022] [Indexed: 01/25/2023]
Abstract
Modeling splicing is essential for tackling the challenge of variant interpretation as each nucleotide variation can be pathogenic by affecting pre-mRNA splicing via disruption/creation of splicing motifs such as 5'/3' splice sites, branch sites, or splicing regulatory elements. Unfortunately, most in silico tools focus on a specific type of splicing motif, which is why we developed the Splicing Prediction Pipeline (SPiP) to perform, in one single bioinformatic analysis based on a machine learning approach, a comprehensive assessment of the variant effect on different splicing motifs. We gathered a curated set of 4616 variants scattered all along the sequence of 227 genes, with their corresponding splicing studies. The Bayesian analysis provided us with the number of control variants, that is, variants without impact on splicing, to mimic the deluge of variants from high-throughput sequencing data. Results show that SPiP can deal with the diversity of splicing alterations, with 83.13% sensitivity and 99% specificity to detect spliceogenic variants. Overall performance as measured by area under the receiving operator curve was 0.986, better than SpliceAI and SQUIRLS (0.965 and 0.766) for the same data set. SPiP lends itself to a unique suite for comprehensive prediction of spliceogenicity in the genomic medicine era. SPiP is available at: https://sourceforge.net/projects/splicing-prediction-pipeline/.
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Affiliation(s)
- Raphaël Leman
- Laboratoire de Biologie et Génétique du CancerCentre François BaclesseCaenFrance
- Inserm U1245, UNIROUEN, FHU‐G4 génomiqueNormandie UniversitéRouenFrance
- UNICAENNormandie UniversitéCaenFrance
| | - Béatrice Parfait
- Service de Génétique et Biologie Moléculaires, APHP, HUPCHôpital CochinParisFrance
| | - Dominique Vidaud
- Service de Génétique et Biologie Moléculaires, APHP, HUPCHôpital CochinParisFrance
| | - Emmanuelle Girodon
- Service de Génétique et Biologie Moléculaires, APHP, HUPCHôpital CochinParisFrance
| | - Laurence Pacot
- Service de Génétique et Biologie Moléculaires, APHP, HUPCHôpital CochinParisFrance
| | - Gérald Le Gac
- Inserm UMR1078, Genetics, Functional Genomics and BiotechnologyUniversité de Bretagne OccidentaleBrestFrance
| | - Chandran Ka
- Inserm UMR1078, Genetics, Functional Genomics and BiotechnologyUniversité de Bretagne OccidentaleBrestFrance
| | - Claude Ferec
- Inserm UMR1078, Genetics, Functional Genomics and BiotechnologyUniversité de Bretagne OccidentaleBrestFrance
| | - Yann Fichou
- Inserm UMR1078, Genetics, Functional Genomics and BiotechnologyUniversité de Bretagne OccidentaleBrestFrance
| | - Céline Quesnelle
- Laboratoire de Biologie et Génétique du CancerCentre François BaclesseCaenFrance
| | - Camille Aucouturier
- Laboratoire de Biologie et Génétique du CancerCentre François BaclesseCaenFrance
- Inserm U1245, UNIROUEN, FHU‐G4 génomiqueNormandie UniversitéRouenFrance
| | - Etienne Muller
- Laboratoire de Biologie et Génétique du CancerCentre François BaclesseCaenFrance
| | - Dominique Vaur
- Laboratoire de Biologie et Génétique du CancerCentre François BaclesseCaenFrance
- Inserm U1245, UNIROUEN, FHU‐G4 génomiqueNormandie UniversitéRouenFrance
| | - Laurent Castera
- Laboratoire de Biologie et Génétique du CancerCentre François BaclesseCaenFrance
- Inserm U1245, UNIROUEN, FHU‐G4 génomiqueNormandie UniversitéRouenFrance
| | - Flavie Boulouard
- Laboratoire de Biologie et Génétique du CancerCentre François BaclesseCaenFrance
- Inserm U1245, UNIROUEN, FHU‐G4 génomiqueNormandie UniversitéRouenFrance
| | - Agathe Ricou
- Laboratoire de Biologie et Génétique du CancerCentre François BaclesseCaenFrance
- Inserm U1245, UNIROUEN, FHU‐G4 génomiqueNormandie UniversitéRouenFrance
| | - Hélène Tubeuf
- Inserm U1245, UNIROUEN, FHU‐G4 génomiqueNormandie UniversitéRouenFrance
- Integrative BiosoftwareRouenFrance
| | - Omar Soukarieh
- Inserm U1245, UNIROUEN, FHU‐G4 génomiqueNormandie UniversitéRouenFrance
| | | | - Florence Riant
- Laboratoire de Génétique, AP‐HPGH Saint‐Louis‐Lariboisière‐Fernand WidalParisFrance
| | | | - Sandrine M. Caputo
- Department of Genetics, Institut CurieParis Sciences Lettres Research UniversityParisFrance
| | | | - Nadia Boutry‐Kryza
- Unité Mixte de Génétique Constitutionnelle des Cancers FréquentsHospices Civils de LyonLyonFrance
| | - Françoise Bonnet‐Dorion
- Departement de Biopathologie Unité de Génétique ConstitutionnelleInstitut Bergonie—INSERM U1218BordeauxFrance
| | - Ines Schultz
- Laboratoire d'OncogénétiqueCentre Paul StraussStrasbourgFrance
| | - Maria Rossing
- Centre for Genomic Medicine, RigshospitaletUniversity of CopenhagenCopenhagenDenmark
| | - Olivier Quenez
- Inserm U1245, UNIROUEN, FHU‐G4 génomiqueNormandie UniversitéRouenFrance
| | - Louis Goldenberg
- Inserm U1245, UNIROUEN, FHU‐G4 génomiqueNormandie UniversitéRouenFrance
| | - Valentin Harter
- Department of BiostatisticsBaclesse Unicancer CenterCaenFrance
| | - Michael T. Parsons
- Department of Genetics and Computational BiologyQIMR Berghofer Medical Research InstituteHerstonQueenslandAustralia
| | - Amanda B. Spurdle
- Department of Genetics and Computational BiologyQIMR Berghofer Medical Research InstituteHerstonQueenslandAustralia
| | - Thierry Frébourg
- Inserm U1245, UNIROUEN, FHU‐G4 génomiqueNormandie UniversitéRouenFrance
- Department of geneticsRouen University HospitalRouenFrance
| | - Alexandra Martins
- Inserm U1245, UNIROUEN, FHU‐G4 génomiqueNormandie UniversitéRouenFrance
| | - Claude Houdayer
- Inserm U1245, UNIROUEN, FHU‐G4 génomiqueNormandie UniversitéRouenFrance
- Department of geneticsRouen University HospitalRouenFrance
| | - Sophie Krieger
- Laboratoire de Biologie et Génétique du CancerCentre François BaclesseCaenFrance
- Inserm U1245, UNIROUEN, FHU‐G4 génomiqueNormandie UniversitéRouenFrance
- UNICAENNormandie UniversitéCaenFrance
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13
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Morak M, Pineda M, Martins A, Gaildrat P, Tubeuf H, Drouet A, Gómez C, Dámaso E, Schaefer K, Steinke-Lange V, Koehler U, Laner A, Hauchard J, Chauris K, Holinski-Feder E, Capellá G. Splicing analyses for variants in MMR genes: best practice recommendations from the European Mismatch Repair Working Group. Eur J Hum Genet 2022; 30:1051-1059. [PMID: 35676339 PMCID: PMC9437034 DOI: 10.1038/s41431-022-01106-w] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2021] [Revised: 03/20/2022] [Accepted: 04/11/2022] [Indexed: 11/09/2022] Open
Abstract
Over 20% of the DNA mismatch repair (MMR) germline variants in suspected Lynch syndrome patients are classified as variants of uncertain significance (VUS). Well-established functional assays are pivotal for assessing the biological impact of these variants and provide relevant evidence for clinical classification. In our collaborative European Mismatch Repair Working Group (EMMR-WG) we compared three different experimental approaches for evaluating the effect of seven variants on mRNA splicing in MMR genes: (i) RT-PCR of full-length transcripts (FLT), (ii) RT-PCR of targeted transcript sections (TTS), both from patient biological samples and (iii) minigene splicing assays. An overall good concordance was observed between splicing patterns in TTS, FLT and minigene analyses for all variants. The FLT analysis depicted a higher number of different isoforms and mitigated PCR-bias towards shorter isoforms. TTS analyses may miss aberrant isoforms and minigene assays may under/overestimate the severity of certain splicing defects. The interpretation of the experimental findings must be cautious to adequately discriminate abnormal events from physiological complex alternative splicing patterns. A consensus strategy for investigating the impact of MMR variants on splicing was defined. First, RNA should be obtained from patient's cell cultures (such as fresh lymphocyte cultures) incubated with/without a nonsense-mediated decay inhibitor. Second, FLT RT-PCR analysis is recommended to oversee all generated isoforms. Third, TTS analysis and minigene assays are useful independent approaches for verifying and clarifying FLT results. The use of several methodologies is likely to increase the strength of the experimental evidence which contributes to improve variant interpretation.
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Affiliation(s)
- Monika Morak
- Medizinische Klinik und Poliklinik IV, Campus Innenstadt, Klinikum der Universität München, Munich, Germany.,MGZ - Medizinisch Genetisches Zentrum, Munich, Germany
| | - Marta Pineda
- Hereditary Cancer Program, Catalan Institute of Oncology-IDIBELL, ONCOBELL Program, L'Hospitalet, Barcelona, Spain.,Centro de Investigación Biomédica en Red de Cáncer (CIBERONC), Madrid, Spain
| | | | | | - Hélène Tubeuf
- Inserm U1245, UNIROUEN, Normandie Univ, F-76000, Rouen, France.,Interactive Biosoftware, Rouen, France
| | - Aurélie Drouet
- Inserm U1245, UNIROUEN, Normandie Univ, F-76000, Rouen, France
| | - Carolina Gómez
- Hereditary Cancer Program, Catalan Institute of Oncology-IDIBELL, ONCOBELL Program, L'Hospitalet, Barcelona, Spain
| | - Estela Dámaso
- Hereditary Cancer Program, Catalan Institute of Oncology-IDIBELL, ONCOBELL Program, L'Hospitalet, Barcelona, Spain
| | - Kerstin Schaefer
- Medizinische Klinik und Poliklinik IV, Campus Innenstadt, Klinikum der Universität München, Munich, Germany
| | - Verena Steinke-Lange
- Medizinische Klinik und Poliklinik IV, Campus Innenstadt, Klinikum der Universität München, Munich, Germany.,MGZ - Medizinisch Genetisches Zentrum, Munich, Germany
| | - Udo Koehler
- MGZ - Medizinisch Genetisches Zentrum, Munich, Germany
| | - Andreas Laner
- MGZ - Medizinisch Genetisches Zentrum, Munich, Germany
| | - Julie Hauchard
- Inserm U1245, UNIROUEN, Normandie Univ, F-76000, Rouen, France
| | - Karine Chauris
- Inserm U1245, UNIROUEN, Normandie Univ, F-76000, Rouen, France
| | - Elke Holinski-Feder
- Medizinische Klinik und Poliklinik IV, Campus Innenstadt, Klinikum der Universität München, Munich, Germany. .,MGZ - Medizinisch Genetisches Zentrum, Munich, Germany.
| | - Gabriel Capellá
- Hereditary Cancer Program, Catalan Institute of Oncology-IDIBELL, ONCOBELL Program, L'Hospitalet, Barcelona, Spain. .,Centro de Investigación Biomédica en Red de Cáncer (CIBERONC), Madrid, Spain.
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14
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Poncet AF, Grunewald O, Vaclavik V, Meunier I, Drumare I, Pelletier V, Bocquet B, Todorova MG, Le Moing AG, Devos A, Schorderet DF, Jobic F, Defoort-Dhellemmes S, Dollfus H, Smirnov VM, Dhaenens CM. Contribution of Whole-Genome Sequencing and Transcript Analysis to Decipher Retinal Diseases Associated with MFSD8 Variants. Int J Mol Sci 2022; 23:ijms23084294. [PMID: 35457110 PMCID: PMC9032189 DOI: 10.3390/ijms23084294] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Revised: 03/25/2022] [Accepted: 04/11/2022] [Indexed: 01/01/2023] Open
Abstract
Biallelic gene defects in MFSD8 are not only a cause of the late-infantile form of neuronal ceroid lipofuscinosis, but also of rare isolated retinal degeneration. We report clinical and genetic data of seven patients compound heterozygous or homozygous for variants in MFSD8, issued from a French cohort with inherited retinal degeneration, and two additional patients retrieved from a Swiss cohort. Next-generation sequencing of large panels combined with whole-genome sequencing allowed for the identification of twelve variants from which seven were novel. Among them were one deep intronic variant c.998+1669A>G, one large deletion encompassing exon 9 and 10, and a silent change c.750A>G. Transcript analysis performed on patients’ lymphoblastoid cell lines revealed the creation of a donor splice site by c.998+1669A>G, resulting in a 140 bp pseudoexon insertion in intron 10. Variant c.750A>G produced exon 8 skipping. In silico and in cellulo studies of these variants allowed us to assign the pathogenic effect, and showed that the combination of at least one severe variant with a moderate one leads to isolated retinal dystrophy, whereas the combination in trans of two severe variants is responsible for early onset severe retinal dystrophy in the context of late-infantile neuronal ceroid lipofuscinosis.
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Affiliation(s)
- Anaïs F. Poncet
- Univ. Lille, Inserm, CHU Lille, U1172-LilNCog-Lille Neuroscience & Cognition, F-59000 Lille, France; (A.F.P.); (O.G.); (A.D.)
| | - Olivier Grunewald
- Univ. Lille, Inserm, CHU Lille, U1172-LilNCog-Lille Neuroscience & Cognition, F-59000 Lille, France; (A.F.P.); (O.G.); (A.D.)
| | - Veronika Vaclavik
- University of Lausanne, Jules-Gonin Eye Hospital, 1004 Lausanne, Switzerland;
- Cantonal Hospital, Department of Ophthalmology, 1700 Fribourg, Switzerland
| | - Isabelle Meunier
- National Reference Centre for Inherited Sensory Diseases, University of Montpellier, Montpellier University Hospital, Sensgene Care Network, ERN-EYE Network, F-34000 Montpellier, France; (I.M.); (B.B.)
- Institute for Neurosciences of Montpellier (INM), University of Montpellier, INSERM, F-34000 Montpellier, France
| | - Isabelle Drumare
- Exploration de la Vision et Neuro-Ophtalmology, CHU de Lille, F-59000 Lille, France; (I.D.); (S.D.-D.); (V.M.S.)
| | - Valérie Pelletier
- Centre de Référence pour les Affections Rares en Génétique Ophtalmologiques, Hopitaux Universitaires de Strasbourg, F-67000 Strasbourg, France; (V.P.); (H.D.)
| | - Béatrice Bocquet
- National Reference Centre for Inherited Sensory Diseases, University of Montpellier, Montpellier University Hospital, Sensgene Care Network, ERN-EYE Network, F-34000 Montpellier, France; (I.M.); (B.B.)
- Institute for Neurosciences of Montpellier (INM), University of Montpellier, INSERM, F-34000 Montpellier, France
| | - Margarita G. Todorova
- Department of Ophthalmology, Cantonal Hospital, 9007 St. Gallen, Switzerland;
- Department of Ophthalmology, University of Zürich, 8091 Zürich, Switzerland
- Department of Ophthalmology, University of Basel, 4056 Basel, Switzerland
| | - Anne-Gaëlle Le Moing
- Department of Child Neurology, Amiens-Picardy University Hospital, F-80000 Amiens, France;
| | - Aurore Devos
- Univ. Lille, Inserm, CHU Lille, U1172-LilNCog-Lille Neuroscience & Cognition, F-59000 Lille, France; (A.F.P.); (O.G.); (A.D.)
| | - Daniel F. Schorderet
- Faculty of Biology and Medicine, University of Lausanne and Faculty of Life Sciences, Ecole Polytechnique Fédérale of Lausanne, 1004 Lausanne, Switzerland;
| | - Florence Jobic
- Unité de Génétique Médicale et Oncogénétique, Centre Hospitalier Universitaire Amiens Picardie, F-80000 Amiens, France;
| | - Sabine Defoort-Dhellemmes
- Exploration de la Vision et Neuro-Ophtalmology, CHU de Lille, F-59000 Lille, France; (I.D.); (S.D.-D.); (V.M.S.)
| | - Hélène Dollfus
- Centre de Référence pour les Affections Rares en Génétique Ophtalmologiques, Hopitaux Universitaires de Strasbourg, F-67000 Strasbourg, France; (V.P.); (H.D.)
| | - Vasily M. Smirnov
- Exploration de la Vision et Neuro-Ophtalmology, CHU de Lille, F-59000 Lille, France; (I.D.); (S.D.-D.); (V.M.S.)
- Université de Lille, Faculté de Médecine, F-59000 Lille, France
| | - Claire-Marie Dhaenens
- Univ. Lille, Inserm, CHU Lille, U1172-LilNCog-Lille Neuroscience & Cognition, F-59000 Lille, France; (A.F.P.); (O.G.); (A.D.)
- Correspondence: ; Tel.: +33-320444953
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15
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Keegan NP, Wilton SD, Fletcher S. Analysis of Pathogenic Pseudoexons Reveals Novel Mechanisms Driving Cryptic Splicing. Front Genet 2022; 12:806946. [PMID: 35140743 PMCID: PMC8819188 DOI: 10.3389/fgene.2021.806946] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Accepted: 12/09/2021] [Indexed: 12/16/2022] Open
Abstract
Understanding pre-mRNA splicing is crucial to accurately diagnosing and treating genetic diseases. However, mutations that alter splicing can exert highly diverse effects. Of all the known types of splicing mutations, perhaps the rarest and most difficult to predict are those that activate pseudoexons, sometimes also called cryptic exons. Unlike other splicing mutations that either destroy or redirect existing splice events, pseudoexon mutations appear to create entirely new exons within introns. Since exon definition in vertebrates requires coordinated arrangements of numerous RNA motifs, one might expect that pseudoexons would only arise when rearrangements of intronic DNA create novel exons by chance. Surprisingly, although such mutations do occur, a far more common cause of pseudoexons is deep-intronic single nucleotide variants, raising the question of why these latent exon-like tracts near the mutation sites have not already been purged from the genome by the evolutionary advantage of more efficient splicing. Possible answers may lie in deep intronic splicing processes such as recursive splicing or poison exon splicing. Because these processes utilize intronic motifs that benignly engage with the spliceosome, the regions involved may be more susceptible to exonization than other intronic regions would be. We speculated that a comprehensive study of reported pseudoexons might detect alignments with known deep intronic splice sites and could also permit the characterisation of novel pseudoexon categories. In this report, we present and analyse a catalogue of over 400 published pseudoexon splice events. In addition to confirming prior observations of the most common pseudoexon mutation types, the size of this catalogue also enabled us to suggest new categories for some of the rarer types of pseudoexon mutation. By comparing our catalogue against published datasets of non-canonical splice events, we also found that 15.7% of pseudoexons exhibit some splicing activity at one or both of their splice sites in non-mutant cells. Importantly, this included seven examples of experimentally confirmed recursive splice sites, confirming for the first time a long-suspected link between these two splicing phenomena. These findings have the potential to improve the fidelity of genetic diagnostics and reveal new targets for splice-modulating therapies.
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Affiliation(s)
- Niall P. Keegan
- Centre for Molecular Medicine and Innovative Therapeutics, Health Futures Institute, Murdoch University, Perth, WA, Australia
- Centre for Neuromuscular and Neurological Disorders, Perron Institute for Neurological and Translational Science, The University of Western Australia, Perth, WA, Australia
- *Correspondence: Niall P. Keegan,
| | - Steve D. Wilton
- Centre for Molecular Medicine and Innovative Therapeutics, Health Futures Institute, Murdoch University, Perth, WA, Australia
- Centre for Neuromuscular and Neurological Disorders, Perron Institute for Neurological and Translational Science, The University of Western Australia, Perth, WA, Australia
| | - Sue Fletcher
- Centre for Molecular Medicine and Innovative Therapeutics, Health Futures Institute, Murdoch University, Perth, WA, Australia
- Centre for Neuromuscular and Neurological Disorders, Perron Institute for Neurological and Translational Science, The University of Western Australia, Perth, WA, Australia
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Geysels RC, Bernal Barquero CE, Martín M, Peyret V, Nocent M, Sobrero G, Muñoz L, Signorino M, Testa G, Castro RB, Masini-Repiso AM, Miras MB, Nicola JP. Silent but Not Harmless: A Synonymous SLC5A5 Gene Variant Leading to Dyshormonogenic Congenital Hypothyroidism. Front Endocrinol (Lausanne) 2022; 13:868891. [PMID: 35600585 PMCID: PMC9114739 DOI: 10.3389/fendo.2022.868891] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/03/2022] [Accepted: 03/23/2022] [Indexed: 12/25/2022] Open
Abstract
BACKGROUND Congenital iodide transport defect (ITD) is an uncommon cause of dyshormonogenic congenital hypothyroidism characterized by the absence of active iodide accumulation in the thyroid gland. ITD is an autosomal recessive disorder caused by loss-of-function variants in the sodium/iodide symporter (NIS)-coding SLC5A5 gene. OBJECTIVE We aimed to identify, and if so to functionally characterize, novel ITD-causing SLC5A5 gene variants in a cohort of five unrelated pediatric patients diagnosed with dyshormonogenic congenital hypothyroidism with minimal to absent 99mTc-pertechnetate accumulation in the thyroid gland. METHODS The coding region of the SLC5A5 gene was sequenced using Sanger sequencing. In silico analysis and functional in vitro characterization of a novel synonymous variant were performed. RESULTS Sanger sequencing revealed a novel homozygous synonymous SLC5A5 gene variant (c.1326A>C in exon 11). In silico analysis revealed that the c.1326A>C variant is potentially deleterious for NIS pre-mRNA splicing. The c.1326A>C variant was predicted to lie within a putative exonic splicing enhancer reducing the binding of splicing regulatory trans-acting protein SRSF5. Splicing minigene reporter assay revealed that c.1326A>C causes exon 11 or exon 11 and 12 skipping during NIS pre-mRNA splicing leading to the NIS pathogenic variants p.G415_P443del and p.G415Lfs*32, respectively. Significantly, the frameshift variant p.G415Lfs*32 is predicted to be subjected to degradation by nonsense-mediated decay. CONCLUSIONS We identified the first exonic synonymous SLC5A5 gene variant causing aberrant NIS pre-mRNA splicing, thus expanding the mutational landscape of the SLC5A5 gene leading to dyshormonogenic congenital hypothyroidism.
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Affiliation(s)
- Romina Celeste Geysels
- Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina
- Centro de Investigaciones en Bioquímica Clínica e Inmunología - Consejo Nacional de Investigaciones Científicas y Técnicas (CIBICI-CONICET), Córdoba, Argentina
| | - Carlos Eduardo Bernal Barquero
- Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina
- Centro de Investigaciones en Bioquímica Clínica e Inmunología - Consejo Nacional de Investigaciones Científicas y Técnicas (CIBICI-CONICET), Córdoba, Argentina
| | - Mariano Martín
- Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina
- Centro de Investigaciones en Bioquímica Clínica e Inmunología - Consejo Nacional de Investigaciones Científicas y Técnicas (CIBICI-CONICET), Córdoba, Argentina
| | - Victoria Peyret
- Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina
- Centro de Investigaciones en Bioquímica Clínica e Inmunología - Consejo Nacional de Investigaciones Científicas y Técnicas (CIBICI-CONICET), Córdoba, Argentina
| | - Martina Nocent
- Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina
- Centro de Investigaciones en Bioquímica Clínica e Inmunología - Consejo Nacional de Investigaciones Científicas y Técnicas (CIBICI-CONICET), Córdoba, Argentina
| | - Gabriela Sobrero
- Programa Provincial de Pesquisa Neonatal, Servicio de Endocrinología, Hospital de Niños de la Santísima Trinidad de Córdoba, Córdoba, Argentina
| | - Liliana Muñoz
- Programa Provincial de Pesquisa Neonatal, Servicio de Endocrinología, Hospital de Niños de la Santísima Trinidad de Córdoba, Córdoba, Argentina
| | - Malvina Signorino
- Programa Provincial de Pesquisa Neonatal, Servicio de Endocrinología, Hospital de Niños de la Santísima Trinidad de Córdoba, Córdoba, Argentina
| | - Graciela Testa
- Programa Provincial de Pesquisa Neonatal, Servicio de Endocrinología, Hospital de Niños de la Santísima Trinidad de Córdoba, Córdoba, Argentina
| | | | - Ana María Masini-Repiso
- Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina
- Centro de Investigaciones en Bioquímica Clínica e Inmunología - Consejo Nacional de Investigaciones Científicas y Técnicas (CIBICI-CONICET), Córdoba, Argentina
| | - Mirta Beatriz Miras
- Programa Provincial de Pesquisa Neonatal, Servicio de Endocrinología, Hospital de Niños de la Santísima Trinidad de Córdoba, Córdoba, Argentina
| | - Juan Pablo Nicola
- Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina
- Centro de Investigaciones en Bioquímica Clínica e Inmunología - Consejo Nacional de Investigaciones Científicas y Técnicas (CIBICI-CONICET), Córdoba, Argentina
- *Correspondence: Juan Pablo Nicola,
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Vaché C, Baux D, Bianchi J, Baudoin C, Faugère V, Francannet C, Koenig M, Kalatzis V, Roux AF. Reclassification of a TMC1 synonymous substitution as a variant disrupting splicing regulatory elements associated with recessive hearing loss. Eur J Hum Genet 2022; 30:34-41. [PMID: 34857896 PMCID: PMC8738754 DOI: 10.1038/s41431-021-01010-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Revised: 11/15/2021] [Accepted: 11/18/2021] [Indexed: 01/03/2023] Open
Abstract
Alterations of the transmembrane channel-like 1 gene (TMC1) are involved in autosomal recessive and dominant nonsyndromic hearing loss (NSHL). To date, up to 117 causal variants including substitutions, insertions and splice variants have been reported in families from different populations. In a patient suffering from severe prelingual NSHL, we identified, in the homozygous state, the previously considered likely benign synonymous c.627C>T; p.(Leu209=) substitution. We used in silico tools predicting variant-induced alterations of splicing regulatory elements (SREs) and pinpointed this transition as a candidate splice-altering variation. Functional splicing analysis, using a minigene assay, confirmed that the variant altered a critical regulatory sequence which is essential for the exon 11 inclusion in the TMC1 transcripts. This result was reinforced by the analysis of orthologous TMC1 mammalian sequences for which the deleterious effect on the mRNA processing of a native thymidine was always counteracted by the presence of a stronger donor splice site or additional enhancer motifs. This study demonstrates, for the first time, the pathogenicity of the c.627C>T alteration leading to its reclassification as a causal variant impacting SREs and highlights the major importance of exhaustive studies to accurately evaluate the pathogenicity of a variant, regardless of the variation type.
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Affiliation(s)
- Christel Vaché
- grid.157868.50000 0000 9961 060XMolecular Genetics Laboratory, Univ Montpellier, CHU Montpellier, Montpellier, France ,grid.121334.60000 0001 2097 0141Institute for Neurosciences of Montpellier, Univ Montpellier, Inserm, Montpellier, France
| | - David Baux
- grid.157868.50000 0000 9961 060XMolecular Genetics Laboratory, Univ Montpellier, CHU Montpellier, Montpellier, France ,grid.121334.60000 0001 2097 0141Institute for Neurosciences of Montpellier, Univ Montpellier, Inserm, Montpellier, France
| | - Julie Bianchi
- grid.157868.50000 0000 9961 060XMolecular Genetics Laboratory, Univ Montpellier, CHU Montpellier, Montpellier, France
| | - Corinne Baudoin
- grid.157868.50000 0000 9961 060XMolecular Genetics Laboratory, Univ Montpellier, CHU Montpellier, Montpellier, France
| | - Valérie Faugère
- grid.157868.50000 0000 9961 060XMolecular Genetics Laboratory, Univ Montpellier, CHU Montpellier, Montpellier, France
| | - Christine Francannet
- grid.411163.00000 0004 0639 4151Department of Medical Genetics, Estaing Hospital, CHU Clermont-Ferrand, Clermont-Ferrand, France
| | - Michel Koenig
- grid.157868.50000 0000 9961 060XMolecular Genetics Laboratory, Univ Montpellier, CHU Montpellier, Montpellier, France
| | - Vasiliki Kalatzis
- grid.121334.60000 0001 2097 0141Institute for Neurosciences of Montpellier, Univ Montpellier, Inserm, Montpellier, France
| | - Anne-Françoise Roux
- grid.157868.50000 0000 9961 060XMolecular Genetics Laboratory, Univ Montpellier, CHU Montpellier, Montpellier, France ,grid.121334.60000 0001 2097 0141Institute for Neurosciences of Montpellier, Univ Montpellier, Inserm, Montpellier, France
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18
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Petersen USS, Doktor TK, Andresen BS. Pseudoexon activation in disease by non-splice site deep intronic sequence variation - wild type pseudoexons constitute high-risk sites in the human genome. Hum Mutat 2021; 43:103-127. [PMID: 34837434 DOI: 10.1002/humu.24306] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2021] [Revised: 11/02/2021] [Accepted: 11/06/2021] [Indexed: 12/27/2022]
Abstract
Accuracy of pre-messenger RNA (pre-mRNA) splicing is crucial for normal gene expression. Complex regulation supports the spliceosomal distinction between authentic exons and the many seemingly functional splice sites delimiting pseudoexons. Pseudoexons are nonfunctional intronic sequences that can be activated for aberrant inclusion in mRNA, which may cause disease. Pseudoexon activation is very challenging to predict, in particular when activation occurs by sequence variants that alter the splicing regulatory environment without directly affecting splice sites. As pseudoexon inclusion often evades detection due to activation of nonsense-mediated mRNA decay, and because conventional diagnostic procedures miss deep intronic sequence variation, pseudoexon activation is a heavily underreported disease mechanism. Pseudoexon characteristics have mainly been studied based on in silico predicted sequences. Moreover, because recognition of sequence variants that create or strengthen splice sites is possible by comparison with well-established consensus sequences, this type of pseudoexon activation is by far the most frequently reported. Here we review all known human disease-associated pseudoexons that carry functional splice sites and are activated by deep intronic sequence variants located outside splice site sequences. We delineate common characteristics that make this type of wild type pseudoexons distinct high-risk sites in the human genome.
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Affiliation(s)
- Ulrika S S Petersen
- Department of Biochemistry and Molecular Biology and the Villum Center for Bioanalytical Sciences, University of Southern Denmark, Odense M, Denmark
| | - Thomas K Doktor
- Department of Biochemistry and Molecular Biology and the Villum Center for Bioanalytical Sciences, University of Southern Denmark, Odense M, Denmark
| | - Brage S Andresen
- Department of Biochemistry and Molecular Biology and the Villum Center for Bioanalytical Sciences, University of Southern Denmark, Odense M, Denmark
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Keegan NP, Fletcher S. A spotter's guide to SNPtic exons: The common splice variants underlying some SNP-phenotype correlations. Mol Genet Genomic Med 2021; 10:e1840. [PMID: 34708937 PMCID: PMC8801146 DOI: 10.1002/mgg3.1840] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Accepted: 10/12/2021] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND Cryptic exons are typically characterised as deleterious splicing aberrations caused by deep intronic mutations. However, low-level splicing of cryptic exons is sometimes observed in the absence of any pathogenic mutation. Five recent reports have described how low-level splicing of cryptic exons can be modulated by common single-nucleotide polymorphisms (SNPs), resulting in phenotypic differences amongst different genotypes. METHODS We sought to investigate whether additional 'SNPtic' exons may exist, and whether these could provide an explanatory mechanism for some of the genotype-phenotype correlations revealed by genome-wide association studies. We thoroughly searched the literature for reported cryptic exons, cross-referenced their genomic coordinates against the dbSNP database of common SNPs, then screened out SNPs with no reported phenotype associations. RESULTS This method discovered five probable SNPtic exons in the genes APC, FGB, GHRL, MYPBC3 and OTC. For four of these five exons, we observed that the phenotype associated with the SNP was compatible with the predicted splicing effect of the nucleotide change, whilst the fifth (in GHRL) likely had a more complex splice-switching effect. CONCLUSION Application of our search methods could augment the knowledge value of future cryptic exon reports and aid in generating better hypotheses for genome-wide association studies.
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Affiliation(s)
- Niall Patrick Keegan
- Murdoch University, Murdoch, Western Australia, Australia.,Centre for Molecular Medicine and Innovative Therapeutics, Perth, Western Australia, Australia.,Perron Institute, Perth, Western Australia, Australia
| | - Sue Fletcher
- Murdoch University, Murdoch, Western Australia, Australia.,Centre for Molecular Medicine and Innovative Therapeutics, Perth, Western Australia, Australia.,University of Western Australia, Perth, Western Australia, Australia
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20
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An artificial neural network approach integrating plasma proteomics and genetic data identifies PLXNA4 as a new susceptibility locus for pulmonary embolism. Sci Rep 2021; 11:14015. [PMID: 34234248 PMCID: PMC8263618 DOI: 10.1038/s41598-021-93390-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Accepted: 06/21/2021] [Indexed: 02/06/2023] Open
Abstract
Venous thromboembolism is the third common cardiovascular disease and is composed of two entities, deep vein thrombosis (DVT) and its potential fatal form, pulmonary embolism (PE). While PE is observed in ~ 40% of patients with documented DVT, there is limited biomarkers that can help identifying patients at high PE risk. To fill this need, we implemented a two hidden-layers artificial neural networks (ANN) on 376 antibodies and 19 biological traits measured in the plasma of 1388 DVT patients, with or without PE, of the MARTHA study. We used the LIME algorithm to obtain a linear approximate of the resulting ANN prediction model. As MARTHA patients were typed for genotyping DNA arrays, a genome wide association study (GWAS) was conducted on the LIME estimate. Detected single nucleotide polymorphisms (SNPs) were tested for association with PE risk in MARTHA. Main findings were replicated in the EOVT study composed of 143 PE patients and 196 DVT only patients. The derived ANN model for PE achieved an accuracy of 0.89 and 0.79 in our training and testing sets, respectively. A GWAS on the LIME approximate identified a strong statistical association peak (rs1424597: p = 5.3 × 10-7) at the PLXNA4 locus. Homozygote carriers for the rs1424597-A allele were then more frequently observed in PE than in DVT patients from the MARTHA (2% vs. 0.4%, p = 0.005) and the EOVT (3% vs. 0%, p = 0.013) studies. In a sample of 112 COVID-19 patients known to have endotheliopathy leading to acute lung injury and an increased risk of PE, decreased PLXNA4 levels were associated (p = 0.025) with worsened respiratory function. Using an original integrated proteomics and genetics strategy, we identified PLXNA4 as a new susceptibility gene for PE whose exact role now needs to be further elucidated.
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21
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Moles-Fernández A, Domènech-Vivó J, Tenés A, Balmaña J, Diez O, Gutiérrez-Enríquez S. Role of Splicing Regulatory Elements and In Silico Tools Usage in the Identification of Deep Intronic Splicing Variants in Hereditary Breast/Ovarian Cancer Genes. Cancers (Basel) 2021; 13:cancers13133341. [PMID: 34283047 PMCID: PMC8268271 DOI: 10.3390/cancers13133341] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Revised: 06/25/2021] [Accepted: 06/29/2021] [Indexed: 11/30/2022] Open
Abstract
Simple Summary There is a significant percentage of hereditary breast and ovarian cancer (HBOC) cases that remain undiagnosed, because no pathogenic variant is detected through massively parallel sequencing of coding exons and exon-intron boundaries of high-moderate susceptibility risk genes. Deep intronic regions may contain variants affecting RNA splicing, leading ultimately to disease, and hence they may explain several cases where the genetic cause of HBOC is unknown. This study aims to characterize intronic regions to identify a landscape of “exonizable” zones and test the efficiency of two in silico tools to detect deep intronic variants affecting the mRNA splicing process. Abstract The contribution of deep intronic splice-altering variants to hereditary breast and ovarian cancer (HBOC) is unknown. Current computational in silico tools to predict spliceogenic variants leading to pseudoexons have limited efficiency. We assessed the performance of the SpliceAI tool combined with ESRseq scores to identify spliceogenic deep intronic variants by affecting cryptic sites or splicing regulatory elements (SREs) using literature and experimental datasets. Our results with 233 published deep intronic variants showed that SpliceAI, with a 0.05 threshold, predicts spliceogenic deep intronic variants affecting cryptic splice sites, but is less effective in detecting those affecting SREs. Next, we characterized the SRE profiles using ESRseq, showing that pseudoexons are significantly enriched in SRE-enhancers compared to adjacent intronic regions. Although the combination of SpliceAI with ESRseq scores (considering ∆ESRseq and SRE landscape) showed higher sensitivity, the global performance did not improve because of the higher number of false positives. The combination of both tools was tested in a tumor RNA dataset with 207 intronic variants disrupting splicing, showing a sensitivity of 86%. Following the pipeline, five spliceogenic deep intronic variants were experimentally identified from 33 variants in HBOC genes. Overall, our results provide a framework to detect deep intronic variants disrupting splicing.
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Affiliation(s)
- Alejandro Moles-Fernández
- Hereditary Cancer Genetics Group, Vall d’Hebron Institute of Oncology (VHIO), Vall d’Hebron Barcelona Hospital Campus, 08035 Barcelona, Spain; (A.M.-F.); (J.D.-V.); (J.B.)
| | - Joanna Domènech-Vivó
- Hereditary Cancer Genetics Group, Vall d’Hebron Institute of Oncology (VHIO), Vall d’Hebron Barcelona Hospital Campus, 08035 Barcelona, Spain; (A.M.-F.); (J.D.-V.); (J.B.)
| | - Anna Tenés
- Area of Clinical and Molecular Genetics, Vall d’Hebron Hospital Universitari, Vall d’Hebron Barcelona Hospital Campus, 08035 Barcelona, Spain;
| | - Judith Balmaña
- Hereditary Cancer Genetics Group, Vall d’Hebron Institute of Oncology (VHIO), Vall d’Hebron Barcelona Hospital Campus, 08035 Barcelona, Spain; (A.M.-F.); (J.D.-V.); (J.B.)
- Medical Oncology Department, Vall d’Hebron Hospital Universitari, Vall d’Hebron Barcelona Hospital Campus, 08035 Barcelona, Spain
| | - Orland Diez
- Hereditary Cancer Genetics Group, Vall d’Hebron Institute of Oncology (VHIO), Vall d’Hebron Barcelona Hospital Campus, 08035 Barcelona, Spain; (A.M.-F.); (J.D.-V.); (J.B.)
- Area of Clinical and Molecular Genetics, Vall d’Hebron Hospital Universitari, Vall d’Hebron Barcelona Hospital Campus, 08035 Barcelona, Spain;
- Correspondence: (O.D.); (S.G.-E.)
| | - Sara Gutiérrez-Enríquez
- Hereditary Cancer Genetics Group, Vall d’Hebron Institute of Oncology (VHIO), Vall d’Hebron Barcelona Hospital Campus, 08035 Barcelona, Spain; (A.M.-F.); (J.D.-V.); (J.B.)
- Correspondence: (O.D.); (S.G.-E.)
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22
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Bueno-Martínez E, Sanoguera-Miralles L, Valenzuela-Palomo A, Lorca V, Gómez-Sanz A, Carvalho S, Allen J, Infante M, Pérez-Segura P, Lázaro C, Easton DF, Devilee P, Vreeswijk MPG, de la Hoya M, Velasco EA. RAD51D Aberrant Splicing in Breast Cancer: Identification of Splicing Regulatory Elements and Minigene-Based Evaluation of 53 DNA Variants. Cancers (Basel) 2021; 13:2845. [PMID: 34200360 PMCID: PMC8201001 DOI: 10.3390/cancers13112845] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2021] [Revised: 06/01/2021] [Accepted: 06/03/2021] [Indexed: 12/18/2022] Open
Abstract
RAD51D loss-of-function variants increase lifetime risk of breast and ovarian cancer. Splicing disruption is a frequent pathogenic mechanism associated with variants in susceptibility genes. Herein, we have assessed the splicing and clinical impact of splice-site and exonic splicing enhancer (ESE) variants identified through the study of ~113,000 women of the BRIDGES cohort. A RAD51D minigene with exons 2-9 was constructed in splicing vector pSAD. Eleven BRIDGES splice-site variants (selected by MaxEntScan) were introduced into the minigene by site-directed mutagenesis and tested in MCF-7 cells. The 11 variants disrupted splicing, collectively generating 25 different aberrant transcripts. All variants but one produced negligible levels (<3.4%) of the full-length (FL) transcript. In addition, ESE elements of the alternative exon 3 were mapped by testing four overlapping exonic microdeletions (≥30-bp), revealing an ESE-rich interval (c.202_235del) with critical sequences for exon 3 recognition that might have been affected by germline variants. Next, 26 BRIDGES variants and 16 artificial exon 3 single-nucleotide substitutions were also assayed. Thirty variants impaired splicing with variable amounts (0-65.1%) of the FL transcript, although only c.202G>A demonstrated a complete aberrant splicing pattern without the FL transcript. On the other hand, c.214T>C increased efficiency of exon 3 recognition, so only the FL transcript was detected (100%). In conclusion, 41 RAD51D spliceogenic variants (28 of which were from the BRIDGES cohort) were identified by minigene assays. We show that minigene-based mapping of ESEs is a powerful approach for identifying ESE hotspots and ESE-disrupting variants. Finally, we have classified nine variants as likely pathogenic according to ACMG/AMP-based guidelines, highlighting the complex relationship between splicing alterations and variant interpretation.
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Affiliation(s)
- Elena Bueno-Martínez
- Splicing and Genetic Susceptibility to Cancer Laboratory, Unidad de Excelencia Instituto de Biología y Genética Molecular, Consejo Superior de Investigaciones Científicas (CSIC-UVa), 47003 Valladolid, Spain; (E.B.-M.); (L.S.-M.); (A.V.-P.)
| | - Lara Sanoguera-Miralles
- Splicing and Genetic Susceptibility to Cancer Laboratory, Unidad de Excelencia Instituto de Biología y Genética Molecular, Consejo Superior de Investigaciones Científicas (CSIC-UVa), 47003 Valladolid, Spain; (E.B.-M.); (L.S.-M.); (A.V.-P.)
| | - Alberto Valenzuela-Palomo
- Splicing and Genetic Susceptibility to Cancer Laboratory, Unidad de Excelencia Instituto de Biología y Genética Molecular, Consejo Superior de Investigaciones Científicas (CSIC-UVa), 47003 Valladolid, Spain; (E.B.-M.); (L.S.-M.); (A.V.-P.)
| | - Víctor Lorca
- Molecular Oncology Laboratory CIBERONC, IdISSC (Instituto de Investigación Sanitaria del Hospital Clínico San Carlos), Hospital Clinico San Carlos, 28040 Madrid, Spain; (V.L.); (A.G.-S.); (P.P.-S.)
| | - Alicia Gómez-Sanz
- Molecular Oncology Laboratory CIBERONC, IdISSC (Instituto de Investigación Sanitaria del Hospital Clínico San Carlos), Hospital Clinico San Carlos, 28040 Madrid, Spain; (V.L.); (A.G.-S.); (P.P.-S.)
| | - Sara Carvalho
- Centre for Cancer Genetic Epidemiology, Department of Public Health and Primary Care, University of Cambridge, Cambridge CB1 8RN, UK; (S.C.); (J.A.); (D.F.E.)
| | - Jamie Allen
- Centre for Cancer Genetic Epidemiology, Department of Public Health and Primary Care, University of Cambridge, Cambridge CB1 8RN, UK; (S.C.); (J.A.); (D.F.E.)
| | - Mar Infante
- Cancer Genetics, Unidad de Excelencia Instituto de Biología y Genética Molecular (CSIC-UVa), 47003 Valladolid, Spain;
| | - Pedro Pérez-Segura
- Molecular Oncology Laboratory CIBERONC, IdISSC (Instituto de Investigación Sanitaria del Hospital Clínico San Carlos), Hospital Clinico San Carlos, 28040 Madrid, Spain; (V.L.); (A.G.-S.); (P.P.-S.)
| | - Conxi Lázaro
- Hereditary Cancer Program, Catalan Institute of Oncology, IDIBELL and CIBERONC, 08908 Hospitalet de Llobregat, Spain;
| | - Douglas F. Easton
- Centre for Cancer Genetic Epidemiology, Department of Public Health and Primary Care, University of Cambridge, Cambridge CB1 8RN, UK; (S.C.); (J.A.); (D.F.E.)
| | - Peter Devilee
- Department of Human Genetics, Leiden University Medical Center, 2300RC Leiden, The Netherlands; (P.D.); (M.P.G.V.)
| | - Maaike P. G. Vreeswijk
- Department of Human Genetics, Leiden University Medical Center, 2300RC Leiden, The Netherlands; (P.D.); (M.P.G.V.)
| | - Miguel de la Hoya
- Molecular Oncology Laboratory CIBERONC, IdISSC (Instituto de Investigación Sanitaria del Hospital Clínico San Carlos), Hospital Clinico San Carlos, 28040 Madrid, Spain; (V.L.); (A.G.-S.); (P.P.-S.)
| | - Eladio A. Velasco
- Splicing and Genetic Susceptibility to Cancer Laboratory, Unidad de Excelencia Instituto de Biología y Genética Molecular, Consejo Superior de Investigaciones Científicas (CSIC-UVa), 47003 Valladolid, Spain; (E.B.-M.); (L.S.-M.); (A.V.-P.)
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Functional Analysis of the PCCA and PCCB Gene Variants Predicted to Affect Splicing. Int J Mol Sci 2021; 22:ijms22084154. [PMID: 33923806 PMCID: PMC8073151 DOI: 10.3390/ijms22084154] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Revised: 03/29/2021] [Accepted: 04/12/2021] [Indexed: 12/03/2022] Open
Abstract
It is estimated that up to one-third of all variants causing inherited diseases affect splicing; however, their deleterious effects and roles in disease pathogenesis are often not fully characterized. Given their prevalence and the development of various antisense-based splice-modulating approaches, pathogenic splicing variants have become an important object of genomic medicine. To improve the accuracy of variant interpretation in public mutation repositories, we applied the minigene splicing assay to study the effects of 24 variants that were predicted to affect normal splicing in the genes associated with propionic acidemia (PA)—PCCA and PCCB. As a result, 13 variants (including one missense and two synonymous variants) demonstrated a significant alteration of splicing with the predicted deleterious effect at the protein level and were characterized as spliceogenic loss-of-function variants. The analysis of the available data for the studied variants and application of the American College of Medical Genetics and the Association for Molecular Pathology (ACMG/AMP) guidelines allowed us to precisely classify five of the variants and change the pathogenic status of nine. Using the example of the PA genes, we demonstrated the utility of the minigene splicing assay in the fast and effective assessment of the spliceogenic effect for identified variants and highlight the necessity of their standardized classification.
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Saint-Martin C, Cauchois-Le Mière M, Rex E, Soukarieh O, Arnoux JB, Buratti J, Bouvet D, Frébourg T, Gaildrat P, Shyng SL, Bellanné-Chantelot C, Martins A. Functional characterization of ABCC8 variants of unknown significance based on bioinformatics predictions, splicing assays, and protein analyses: Benefits for the accurate diagnosis of congenital hyperinsulinism. Hum Mutat 2021; 42:408-420. [PMID: 33410562 DOI: 10.1002/humu.24164] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Revised: 12/06/2020] [Accepted: 12/31/2020] [Indexed: 12/20/2022]
Abstract
ABCC8 encodes the SUR1 subunit of the β-cell ATP-sensitive potassium channel whose loss of function causes congenital hyperinsulinism (CHI). Molecular diagnosis is critical for optimal management of CHI patients. Unfortunately, assessing the impact of ABCC8 variants on RNA splicing remains very challenging as this gene is poorly expressed in leukocytes. Here, we performed bioinformatics analysis and cell-based minigene assays to assess the impact on splicing of 13 ABCC8 variants identified in 20 CHI patients. Next, channel properties of SUR1 proteins expected to originate from minigene-detected in-frame splicing defects were analyzed after ectopic expression in COSm6 cells. Out of the analyzed variants, seven induced out-of-frame splicing defects and were therefore classified as recessive pathogenic, whereas two led to skipping of in-frame exons. Channel functional analysis of the latter demonstrated their pathogenicity. Interestingly, the common rs757110 SNP increased exon skipping in our system suggesting that it may act as a disease modifier factor. Our strategy allowed determining the pathogenicity of all selected ABCC8 variants, and CHI-inheritance pattern for 16 out of the 20 patients. This study highlights the value of combining RNA and protein functional approaches in variant interpretation and reveals the minigene splicing assay as a new tool for CHI molecular diagnostics.
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Affiliation(s)
- Cécile Saint-Martin
- Department of Genetics, AP-HP Pitié-Salpêtrière Hospital, Sorbonne University, Paris, France
| | - Marine Cauchois-Le Mière
- Inserm U1245, UFR de Médecine et Pharmacie, UNIROUEN, Normandie University, Normandy Centre for Genomic and Personalized Medicine, Rouen, France.,Department of Genetics, University Hospital, Normandy Centre for Genomic and Personalized Medicine, Rouen, France
| | - Emily Rex
- Department of Chemical Physiology and Biochemistry, Oregon Health & Science University, Portland, OR, USA
| | - Omar Soukarieh
- Inserm U1245, UFR de Médecine et Pharmacie, UNIROUEN, Normandie University, Normandy Centre for Genomic and Personalized Medicine, Rouen, France
| | - Jean-Baptiste Arnoux
- Department of Inherited Metabolic Disease, Necker-Enfants Malades University Hospital, AP-HP, Paris, France
| | - Julien Buratti
- Department of Genetics, AP-HP Pitié-Salpêtrière Hospital, Sorbonne University, Paris, France
| | - Delphine Bouvet
- Department of Genetics, AP-HP Pitié-Salpêtrière Hospital, Sorbonne University, Paris, France
| | - Thierry Frébourg
- Inserm U1245, UFR de Médecine et Pharmacie, UNIROUEN, Normandie University, Normandy Centre for Genomic and Personalized Medicine, Rouen, France.,Department of Genetics, University Hospital, Normandy Centre for Genomic and Personalized Medicine, Rouen, France
| | - Pascaline Gaildrat
- Inserm U1245, UFR de Médecine et Pharmacie, UNIROUEN, Normandie University, Normandy Centre for Genomic and Personalized Medicine, Rouen, France
| | - Show-Ling Shyng
- Department of Chemical Physiology and Biochemistry, Oregon Health & Science University, Portland, OR, USA
| | | | - Alexandra Martins
- Inserm U1245, UFR de Médecine et Pharmacie, UNIROUEN, Normandie University, Normandy Centre for Genomic and Personalized Medicine, Rouen, France
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25
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A rare coding mutation in the MAST2 gene causes venous thrombosis in a French family with unexplained thrombophilia: The Breizh MAST2 Arg89Gln variant. PLoS Genet 2021; 17:e1009284. [PMID: 33465109 PMCID: PMC7846112 DOI: 10.1371/journal.pgen.1009284] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Revised: 01/29/2021] [Accepted: 11/18/2020] [Indexed: 11/19/2022] Open
Abstract
Rare variants outside the classical coagulation cascade might cause inherited thrombosis. We aimed to identify the variant(s) causing venous thromboembolism (VTE) in a family with multiple relatives affected with unprovoked VTE and no thrombophilia defects. We identified by whole exome sequencing an extremely rare Arg to Gln variant (Arg89Gln) in the Microtubule Associated Serine/Threonine Kinase 2 (MAST2) gene that segregates with VTE in the family. Free-tissue factor pathway inhibitor (f-TFPI) plasma levels were significantly decreased in affected family members compared to healthy relatives. Conversely, plasminogen activator inhibitor-1 (PAI-1) levels were significantly higher in affected members than in healthy relatives. RNA sequencing analysis of RNA interference experimental data conducted in endothelial cells revealed that, of the 13,387 detected expressed genes, 2,354 have their level of expression modified by MAST2 knockdown, including SERPINE1 coding for PAI-1 and TFPI. In HEK293 cells overexpressing the MAST2 Gln89 variant, TFPI and SERPINE1 promoter activities were respectively lower and higher than in cells overexpressing the MAST2 wild type. This study identifies a novel thrombophilia-causing Arg89Gln variant in the MAST2 gene that is here proposed as a new molecular player in the etiology of VTE by interfering with hemostatic balance of endothelial cells.
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26
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Tubeuf H, Caputo SM, Sullivan T, Rondeaux J, Krieger S, Caux-Moncoutier V, Hauchard J, Castelain G, Fiévet A, Meulemans L, Révillion F, Léoné M, Boutry-Kryza N, Delnatte C, Guillaud-Bataille M, Cleveland L, Reid S, Southon E, Soukarieh O, Drouet A, Di Giacomo D, Vezain M, Bonnet-Dorion F, Bourdon V, Larbre H, Muller D, Pujol P, Vaz F, Audebert-Bellanger S, Colas C, Venat-Bouvet L, Solano AR, Stoppa-Lyonnet D, Houdayer C, Frebourg T, Gaildrat P, Sharan SK, Martins A. Calibration of Pathogenicity Due to Variant-Induced Leaky Splicing Defects by Using BRCA2 Exon 3 as a Model System. Cancer Res 2020; 80:3593-3605. [PMID: 32641407 DOI: 10.1158/0008-5472.can-20-0895] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Revised: 05/14/2020] [Accepted: 07/02/2020] [Indexed: 12/25/2022]
Abstract
BRCA2 is a clinically actionable gene implicated in breast and ovarian cancer predisposition that has become a high priority target for improving the classification of variants of unknown significance (VUS). Among all BRCA2 VUS, those causing partial/leaky splicing defects are the most challenging to classify because the minimal level of full-length (FL) transcripts required for normal function remains to be established. Here, we explored BRCA2 exon 3 (BRCA2e3) as a model for calibrating variant-induced spliceogenicity and estimating thresholds for BRCA2 haploinsufficiency. In silico predictions, minigene splicing assays, patients' RNA analyses, a mouse embryonic stem cell (mESC) complementation assay and retrieval of patient-related information were combined to determine the minimal requirement of FL BRCA2 transcripts. Of 100 BRCA2e3 variants tested in the minigene assay, 64 were found to be spliceogenic, causing mild to severe RNA defects. Splicing defects were also confirmed in patients' RNA when available. Analysis of a neutral leaky variant (c.231T>G) showed that a reduction of approximately 60% of FL BRCA2 transcripts from a mutant allele does not cause any increase in cancer risk. Moreover, data obtained from mESCs suggest that variants causing a decline in FL BRCA2 with approximately 30% of wild-type are not pathogenic, given that mESCs are fully viable and resistant to DNA-damaging agents in those conditions. In contrast, mESCs producing lower relative amounts of FL BRCA2 exhibited either null or hypomorphic phenotypes. Overall, our findings are likely to have broader implications on the interpretation of BRCA2 variants affecting the splicing pattern of other essential exons. SIGNIFICANCE: These findings demonstrate that BRCA2 tumor suppressor function tolerates substantial reduction in full-length transcripts, helping to determine the pathogenicity of BRCA2 leaky splicing variants, some of which may not increase cancer risk.
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Affiliation(s)
- Hélène Tubeuf
- Inserm U1245, UNIROUEN, Normandie University, Normandy Centre for Genomic and Personalized Medicine, Rouen, France.,Interactive Biosoftware, Rouen, France
| | - Sandrine M Caputo
- Department of Genetics, Institut Curie, Paris, France.,PSL Research University, Paris, France
| | - Teresa Sullivan
- Mouse Cancer Genetics Program, Center for Cancer Research, National Cancer Institute, Frederick, Maryland
| | - Julie Rondeaux
- Inserm U1245, UNIROUEN, Normandie University, Normandy Centre for Genomic and Personalized Medicine, Rouen, France
| | - Sophie Krieger
- Inserm U1245, UNIROUEN, Normandie University, Normandy Centre for Genomic and Personalized Medicine, Rouen, France.,Laboratory of Cancer Biology and Genetics, Centre François Baclesse, Caen, France - Normandie University, UNICAEN, Caen, France
| | | | - Julie Hauchard
- Inserm U1245, UNIROUEN, Normandie University, Normandy Centre for Genomic and Personalized Medicine, Rouen, France
| | - Gaia Castelain
- Inserm U1245, UNIROUEN, Normandie University, Normandy Centre for Genomic and Personalized Medicine, Rouen, France
| | - Alice Fiévet
- Department of Genetics, Institut Curie, Paris, France.,INSERM U830, University Paris Descartes, Paris, France.,Service Génétique des Tumeurs, Gustave Roussy, Villejuif, France
| | - Laëtitia Meulemans
- Inserm U1245, UNIROUEN, Normandie University, Normandy Centre for Genomic and Personalized Medicine, Rouen, France
| | | | | | | | | | | | - Linda Cleveland
- Mouse Cancer Genetics Program, Center for Cancer Research, National Cancer Institute, Frederick, Maryland
| | - Susan Reid
- Mouse Cancer Genetics Program, Center for Cancer Research, National Cancer Institute, Frederick, Maryland
| | - Eileen Southon
- Mouse Cancer Genetics Program, Center for Cancer Research, National Cancer Institute, Frederick, Maryland
| | - Omar Soukarieh
- Inserm U1245, UNIROUEN, Normandie University, Normandy Centre for Genomic and Personalized Medicine, Rouen, France
| | - Aurélie Drouet
- Inserm U1245, UNIROUEN, Normandie University, Normandy Centre for Genomic and Personalized Medicine, Rouen, France
| | - Daniela Di Giacomo
- Inserm U1245, UNIROUEN, Normandie University, Normandy Centre for Genomic and Personalized Medicine, Rouen, France
| | - Myriam Vezain
- Inserm U1245, UNIROUEN, Normandie University, Normandy Centre for Genomic and Personalized Medicine, Rouen, France
| | | | - Violaine Bourdon
- Department of Genetics, Institut Paoli-Calmettes, Marseille, France
| | - Hélène Larbre
- Laboratoire d'Oncogénétique Moléculaire, Institut Godinot, Reims, France
| | - Danièle Muller
- Unité d'Oncogénétique, Centre Paul Strauss, Strasbourg, France
| | - Pascal Pujol
- Unité d'Oncogénétique, CHU Arnaud de Villeneuve, Montpellier, France
| | - Fátima Vaz
- Breast Cancer Risk Evaluation Clinic, Portuguese Institute of Oncology of Lisbon, Lisbon, Portugal
| | | | - Chrystelle Colas
- Department of Genetics, Institut Curie, Paris, France.,PSL Research University, Paris, France
| | | | - Angela R Solano
- Genotipificacion y Cancer Hereditario, Departmento de Analisis Clinicos, Centro de Educacion Medica e Investigaciones Clinicas (CEMIC), Ciudad Autonoma de Buenos Aires, Argentina
| | - Dominique Stoppa-Lyonnet
- Department of Genetics, Institut Curie, Paris, France.,INSERM U830, University Paris Descartes, Paris, France
| | - Claude Houdayer
- Inserm U1245, UNIROUEN, Normandie University, Normandy Centre for Genomic and Personalized Medicine, Rouen, France.,Department of Genetics, University Hospital, Normandy Centre for Genomic and Personalized Medicine, Rouen, France
| | - Thierry Frebourg
- Inserm U1245, UNIROUEN, Normandie University, Normandy Centre for Genomic and Personalized Medicine, Rouen, France.,Department of Genetics, University Hospital, Normandy Centre for Genomic and Personalized Medicine, Rouen, France
| | - Pascaline Gaildrat
- Inserm U1245, UNIROUEN, Normandie University, Normandy Centre for Genomic and Personalized Medicine, Rouen, France
| | - Shyam K Sharan
- Mouse Cancer Genetics Program, Center for Cancer Research, National Cancer Institute, Frederick, Maryland
| | - Alexandra Martins
- Inserm U1245, UNIROUEN, Normandie University, Normandy Centre for Genomic and Personalized Medicine, Rouen, France.
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