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Zhang ZYO, Wu YY, Cai XY, Fang WL, Xiao FL. Molecular Diagnosis of Neurofibromatosis by Multigene Panel Testing. Front Genet 2021; 12:603195. [PMID: 33767727 PMCID: PMC7985060 DOI: 10.3389/fgene.2021.603195] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2020] [Accepted: 02/02/2021] [Indexed: 11/13/2022] Open
Abstract
Neurofibromatosis (NF) is an autosomal genetic disorder for which early and definite clinical diagnoses are difficult. To identify the diagnosis, five affected probands with suspected NF from unrelated families were included in this study. Molecular analysis was performed using multigene panel testing and Sanger sequencing. Ultradeep sequencing was used to analyze the mutation rate in the tissues from the proband with mosaic mutations. Three different pathogenic variants of the NF1 gene were found in three probands who mainly complained of café-au-lait macules (CALMs), including one frameshift variant c.5072_5073insTATAACTGTAACTCCTGGGTCAGGGAGTACACCAA:p.Tyr1692Ilefs in exon 37, one missense variant c.3826C > T:p.Arg1276Ter in exon 28, and one splicing variant c.4110 + 1G > T at the first base downstream of the 3′-end of exon 30. One NF1 gene mosaic variant was found in a proband who complained of cutaneous neurofibroma with the frameshift variant c.495_498del:p.Thr165fs in exon 5, and ultradeep sequencing showed the highest mutation rate of 10.81% in cutaneous neurofibromas. A frameshift variant, c.36_39del:p.Ser12fs in exon 1 of the NF2 gene, was found in a proband who presented with skin plaques and intracranial neurogenic tumors. All of these pathogenic variants were heterozygous, one was not reported, and one not in Chinese before. This study expands the pathogenic variant spectrum of NF and demonstrates the clinical diagnosis.
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Affiliation(s)
- Zeng-Yun-Ou Zhang
- Department of Dermatology, First Affiliated Hospital of Anhui Medical University, Hefei, China.,Key Laboratory of Dermatology, Ministry of Education, Anhui Medical University, Hefei, China
| | - Yuan-Yuan Wu
- Department of Dermatology, First Affiliated Hospital of Anhui Medical University, Hefei, China.,Key Laboratory of Dermatology, Ministry of Education, Anhui Medical University, Hefei, China
| | - Xin-Ying Cai
- Department of Dermatology, First Affiliated Hospital of Anhui Medical University, Hefei, China.,Key Laboratory of Dermatology, Ministry of Education, Anhui Medical University, Hefei, China
| | - Wen-Liang Fang
- Clinical College, Anhui Medical University, Hefei, China
| | - Feng-Li Xiao
- Department of Dermatology, First Affiliated Hospital of Anhui Medical University, Hefei, China.,Key Laboratory of Dermatology, Ministry of Education, Anhui Medical University, Hefei, China.,The Center for Scientific Research of Anhui Medical University, Hefei, China
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Bianchessi D, Ibba MC, Saletti V, Blasa S, Langella T, Paterra R, Cagnoli GA, Melloni G, Scuvera G, Natacci F, Cesaretti C, Finocchiaro G, Eoli M. Simultaneous Detection of NF1, SPRED1, LZTR1, and NF2 Gene Mutations by Targeted NGS in an Italian Cohort of Suspected NF1 Patients. Genes (Basel) 2020; 11:genes11060671. [PMID: 32575496 PMCID: PMC7349720 DOI: 10.3390/genes11060671] [Citation(s) in RCA: 2] [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: 05/23/2020] [Revised: 06/12/2020] [Accepted: 06/16/2020] [Indexed: 12/30/2022] Open
Abstract
Neurofibromatosis type 1 (NF1) displays overlapping phenotypes with other neurocutaneous diseases such as Legius Syndrome. Here, we present results obtained using a next generation sequencing (NGS) panel including NF1, NF2, SPRED1, SMARCB1, and LZTR1 genes on Ion Torrent. Together with NGS, the Multiplex Ligation-Dependent Probe Amplification Analysis (MLPA) method was performed to rule out large deletions/duplications in NF1 gene; we validated the MLPA/NGS approach using Sanger sequencing on DNA or RNA of both positive and negative samples. In our cohort, a pathogenic variant was found in 175 patients; the pathogenic variant was observed in NF1 gene in 168 cases. A SPRED1 pathogenic variant was also found in one child and in a one year old boy, both NF2 and LZTR1 pathogenic variants were observed; in addition, we identified five LZTR1 pathogenic variants in three children and two adults. Six NF1 pathogenic variants, that the NGS analysis failed to identify, were detected on RNA by Sanger. NGS allows the identification of novel mutations in five genes in the same sequencing run, permitting unambiguous recognition of disorders with overlapping phenotypes with NF1 and facilitating genetic counseling and a personalized follow-up.
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Affiliation(s)
- Donatella Bianchessi
- Molecular Neuro-Oncology Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, via Celoria 11, 20133 Milan, Italy; (D.B.); (M.C.I.); (S.B.); (T.L.); (R.P.); (G.F.)
| | - Maria Cristina Ibba
- Molecular Neuro-Oncology Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, via Celoria 11, 20133 Milan, Italy; (D.B.); (M.C.I.); (S.B.); (T.L.); (R.P.); (G.F.)
| | - Veronica Saletti
- Developmental Neurology Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, via Celoria 11, 20133 Milan, Italy; (V.S.); (G.M.)
| | - Stefania Blasa
- Molecular Neuro-Oncology Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, via Celoria 11, 20133 Milan, Italy; (D.B.); (M.C.I.); (S.B.); (T.L.); (R.P.); (G.F.)
- Department of Biotechnology and Biosciences, University of Milano-Bicocca, Piazza dell’Ateneo Nuovo, 1, 20126 Milan, Italy
| | - Tiziana Langella
- Molecular Neuro-Oncology Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, via Celoria 11, 20133 Milan, Italy; (D.B.); (M.C.I.); (S.B.); (T.L.); (R.P.); (G.F.)
- Molecular Immunology Unit, Department of Research, Fondazione IRCCS Istituto Nazionale dei Tumori, Via Venezian, 20133 Milan, Italy
| | - Rosina Paterra
- Molecular Neuro-Oncology Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, via Celoria 11, 20133 Milan, Italy; (D.B.); (M.C.I.); (S.B.); (T.L.); (R.P.); (G.F.)
| | - Giulia Anna Cagnoli
- Medical Genetics Unit, Woman-Child-Newborn Department, Fondazione IRCCS Ca’ Granda-Ospedale Maggiore Policlinico, via Francesco Sforza 28, 20122 Milan, Italy; (G.A.C.); (F.N.); (C.C.)
| | - Giulia Melloni
- Developmental Neurology Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, via Celoria 11, 20133 Milan, Italy; (V.S.); (G.M.)
| | - Giulietta Scuvera
- Pediatric Highly Intensive Care Unit, Università degli Studi di Milano, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, via Francesco Sforza 28, 20122 Milan, Italy;
| | - Federica Natacci
- Medical Genetics Unit, Woman-Child-Newborn Department, Fondazione IRCCS Ca’ Granda-Ospedale Maggiore Policlinico, via Francesco Sforza 28, 20122 Milan, Italy; (G.A.C.); (F.N.); (C.C.)
| | - Claudia Cesaretti
- Medical Genetics Unit, Woman-Child-Newborn Department, Fondazione IRCCS Ca’ Granda-Ospedale Maggiore Policlinico, via Francesco Sforza 28, 20122 Milan, Italy; (G.A.C.); (F.N.); (C.C.)
| | - Gaetano Finocchiaro
- Molecular Neuro-Oncology Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, via Celoria 11, 20133 Milan, Italy; (D.B.); (M.C.I.); (S.B.); (T.L.); (R.P.); (G.F.)
| | - Marica Eoli
- Molecular Neuro-Oncology Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, via Celoria 11, 20133 Milan, Italy; (D.B.); (M.C.I.); (S.B.); (T.L.); (R.P.); (G.F.)
- Correspondence:
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3
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Calì F, Chiavetta V, Ruggeri G, Piccione M, Selicorni A, Palazzo D, Bonsignore M, Cereda A, Elia M, Failla P, Figura MG, Fiumara A, Maitz S, Luana Mandarà GM, Mattina T, Ragalmuto A, Romano C, Ruggieri M, Salluzzo R, Saporoso A, Schepis C, Sorge G, Spanò M, Tortorella G, Romano V. Mutation spectrum of NF1 gene in Italian patients with neurofibromatosis type 1 using Ion Torrent PGM™ platform. Eur J Med Genet 2016; 60:93-99. [PMID: 27838393 DOI: 10.1016/j.ejmg.2016.11.001] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2016] [Revised: 10/26/2016] [Accepted: 11/06/2016] [Indexed: 01/06/2023]
Abstract
Neurofibromatosis type 1 (NF1) is caused by mutations of the NF1 gene and is one of the most common human autosomal dominant disorders. The patient shows different signs on the skin and other organs from early childhood. The best known are six or more café au lait spots, axillary or inguinal freckling, increased risk of developing benign nerve sheath tumours and plexiform neurofibromas. Mutation detection is complex, due to the large gene size, the large variety of mutations and the presence of pseudogenes. Using Ion Torrent PGM™ Platform, 73 mutations were identified in 79 NF1 Italian patients, 51% of which turned out to be novel mutations. Pathogenic status of each variant was classified using "American College of Medical Genetics and Genomics" guidelines criteria, thus enabling the classification of 96% of the variants identified as being pathogenic. The use of Next Generation Sequencing has proven to be effective as for costs, and time for analysis, and it allowed us to identify a patient with NF1 mosaicism. Furthermore, we designed a new approach aimed to quantify the mosaicism percentage using electropherogram of capillary electrophoresis performed on Sanger method.
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Affiliation(s)
- Francesco Calì
- Laboratorio di Genetica Molecolare, UOC Laboratorio di Genetica Medica, Associazione Oasi Maria SS, IRCCS, Troina, EN, Italy.
| | - Valeria Chiavetta
- Laboratorio di Genetica Molecolare, UOC Laboratorio di Genetica Medica, Associazione Oasi Maria SS, IRCCS, Troina, EN, Italy
| | - Giuseppa Ruggeri
- Laboratorio di Genetica Molecolare, UOC Laboratorio di Genetica Medica, Associazione Oasi Maria SS, IRCCS, Troina, EN, Italy
| | - Maria Piccione
- Azienda Ospedali Riuniti Villa Sofia Cervello, Università degli Studi di Palermo, Palermo, Italy
| | - Angelo Selicorni
- UOS Genetica Pediatrica, Fondazione MBBM, AOS Gerardo, Monza, Italy; UOC Pediatria ASST Lariana, Como, Italy
| | - Daniela Palazzo
- Azienda Ospedali Riuniti Villa Sofia Cervello, Università degli Studi di Palermo, Palermo, Italy
| | - Maria Bonsignore
- UOC di Neuropsichiatria Infantile, Dipartimento Materno Infantile, Policlinico Universitario "G. Martino", Messina, Italy
| | - Anna Cereda
- UOC Pediatria Ospedale Papa Giovanni XXIII Bergamo, Italy
| | - Maurizio Elia
- Dipartimento per il Ritardo Mentale, Associazione Oasi Maria SS, IRCCS, Troina, EN, Italy
| | - Pinella Failla
- Dipartimento per il Ritardo Mentale, Associazione Oasi Maria SS, IRCCS, Troina, EN, Italy
| | - Maria Grazia Figura
- Dipartimento per il Ritardo Mentale, Associazione Oasi Maria SS, IRCCS, Troina, EN, Italy
| | - Agata Fiumara
- Dipartimento di Medicina Clinica e Sperimentale, Sezione di Pediatria e Neuropsichiatria Infantile, Università degli Studi di Catania, Catania, Italy
| | - Silvia Maitz
- UOS Genetica Pediatrica, Fondazione MBBM, AOS Gerardo, Monza, Italy
| | | | - Teresa Mattina
- Dipartimento di Medicina Clinica e Sperimentale, Sezione di Pediatria e Neuropsichiatria Infantile, Università degli Studi di Catania, Catania, Italy
| | - Alda Ragalmuto
- Laboratorio di Genetica Molecolare, UOC Laboratorio di Genetica Medica, Associazione Oasi Maria SS, IRCCS, Troina, EN, Italy
| | - Corrado Romano
- Dipartimento per il Ritardo Mentale, Associazione Oasi Maria SS, IRCCS, Troina, EN, Italy
| | - Martino Ruggieri
- Dipartimento di Medicina Clinica e Sperimentale, Sezione di Pediatria e Neuropsichiatria Infantile, Università degli Studi di Catania, Catania, Italy
| | - Roberto Salluzzo
- Laboratorio di Genetica Molecolare, UOC Laboratorio di Genetica Medica, Associazione Oasi Maria SS, IRCCS, Troina, EN, Italy
| | - Antonino Saporoso
- UOC di Neuropsichiatria Infantile, Dipartimento Materno Infantile, Policlinico Universitario "G. Martino", Messina, Italy
| | - Carmelo Schepis
- Dipartimento per il Ritardo Mentale, Associazione Oasi Maria SS, IRCCS, Troina, EN, Italy
| | - Giovanni Sorge
- Dipartimento di Medicina Clinica e Sperimentale, Sezione di Pediatria e Neuropsichiatria Infantile, Università degli Studi di Catania, Catania, Italy
| | - Maria Spanò
- UOC di Neuropsichiatria Infantile, Dipartimento Materno Infantile, Policlinico Universitario "G. Martino", Messina, Italy
| | - Gaetano Tortorella
- UOC di Neuropsichiatria Infantile, Dipartimento Materno Infantile, Policlinico Universitario "G. Martino", Messina, Italy
| | - Valentino Romano
- Dipartimento di Fisica e Chimica, Università degli Studi di Palermo, Palermo, Italy
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Yao R, Wang L, Yu Y, Wang J, Shen Y. Diagnostic value of multiple café-au-lait macules for neurofibromatosis 1 in Chinese children. J Dermatol 2015; 43:537-42. [PMID: 26458495 DOI: 10.1111/1346-8138.13169] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2015] [Accepted: 09/03/2015] [Indexed: 11/28/2022]
Abstract
Neurofibromatosis 1 (NF1) is a common autosomal dominant condition caused by mutations in the NF1 gene. The appearance of multiple café-au-lait macules is an early sign of the condition, which often alert physicians to follow up and further examine the patient for the possibility of NF1. In order to determine the predictive value of multiple café-au-lait macules at early age for NF1 in Chinese patients, we recruited 19 children who shared the common sign of multiple café-au-lait macules from a general pediatric clinic in Shanghai. All the patients were clinically evaluated following the National Institutes of Health criteria for NF1 and molecular tested for sequence variants and copy number changes. Nine children met the clinical diagnostic criteria of NF1, and molecular tests confirmed all nine patients with pathogenic variants including two genomic deletions, two novel frame-shift variants, four novel nonsense and a splicing variants. In addition, four children who did not meet the diagnostic criteria were also found to carry pathogenic NF1 variants. Overall, 68.4% (13/19) of children with café-au-lait macules and various other clinical presentations were molecularly confirmed with NF1. This study demonstrated that the majority of Chinese children with multiple café-au-lait macules who came to seek for medical attention had NF1. Molecular testing is necessary to be used as an adjunct and sometimes as the main tool for confirming and diagnosing children of NF1 at early age.
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Affiliation(s)
- Ruen Yao
- Shanghai Children's Medical Center, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Lili Wang
- Xinhua Hospital, Institute for Pediatric Research, Shanghai, China
| | - Yongguo Yu
- Xinhua Hospital, Institute for Pediatric Research, Shanghai, China
| | - Jian Wang
- Shanghai Children's Medical Center, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Yiping Shen
- Shanghai Children's Medical Center, Shanghai Jiaotong University School of Medicine, Shanghai, China.,Boston Children's Hospital, Boston, Massachusetts, USA.,Claritas Genomics, Cambridge, Massachusetts, USA
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Nemethova M, Bolcekova A, Ilencikova D, Durovcikova D, Hlinkova K, Hlavata A, Kovacs L, Kadasi L, Zatkova A. Thirty-nine novel neurofibromatosis 1 (NF1) gene mutations identified in Slovak patients. Ann Hum Genet 2013; 77:364-79. [PMID: 23758643 DOI: 10.1111/ahg.12026] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2012] [Accepted: 04/22/2013] [Indexed: 01/20/2023]
Abstract
We performed a complex analysis of the neurofibromatosis type 1 (NF1) gene in Slovakia based on direct cDNA sequencing supplemented by multiple ligation dependent probe amplification (MLPA) analysis. All 108 patients had café-au-lait spots, 85% had axilary and/or inguinal freckling, 61% neurofibromas, 36% Lisch nodules of the iris and 31% optic pathway glioma, 5% suffered from typical skeletal disorders, and 51% of patients had family members with NF1. In 78 of the 86 (90.7%) index patients our analysis revealed the presence of NF1 mutations, 68 of which were small changes (87.2%), including 39 (50%) novel. Among the identified mutations the most prevalent were small deletions and insertions causing frameshift (42.3%), followed by nonsense (14.1%), missense (12.8%), and typical splicing (11.5%) mutations. Type 1 NF1 deletions and intragenic deletions/duplication were identified in five cases each (6.4%). Interestingly, in five other cases nontypical splicing variants were found, whose real effect on NF1 transcript would have remained undetected if using a DNA-based method alone, thus underlying the advantage of using the cDNA-based sequencing. We show that Slovak NF1 patients have a similar repertoire of NF1 germline mutations compared to other populations, with some prevalence of small deletions/insertions and a decreased proportion of nonsense mutations.
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Affiliation(s)
- Martina Nemethova
- Laboratory of Genetics, Institute of Molecular Physiology and Genetics, Bratislava, Slovakia
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6
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Four-year follow-up study in a NF1 boy with a focal pontine hamartoma. Ital J Pediatr 2013; 39:10. [PMID: 23399325 PMCID: PMC3579694 DOI: 10.1186/1824-7288-39-10] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/29/2012] [Accepted: 02/02/2013] [Indexed: 11/10/2022] Open
Abstract
Neurofibromatosis is a collective name for a group of genetic conditions in which benign tumours affect the nervous system. Type 1 is caused by a genetic mutation in the NF1 gene (OMIM 613113) and symptoms can vary dramatically between individuals, even within the same family. Some people have very mild skin changes, whereas others suffer severe medical complications. The condition usually appears in childhood and is diagnosed if two of the following are present: six or more café-au-lait patches larger than 1.5 cm in diameter, axillary or groin freckling, 2 or more Lisch nodules (small pigmented areas in the iris of the eye), 2 or more neurofibromas, optic pathway gliomas, bone dysplasia, and a first-degree family relative with Neurofibromatosis type 1. The pattern of inheritance is autosomal dominant, however, half of all NF1 cases are ‘sporadic’ and there is no family history. Neurofibromatosis type 1 is an extremely variable condition whose morbidity and mortality is largely dictated by the occurrence of the many complications that may involve any of the body systems. We describe a family affected by NF1 in whom genetic molecular analysis identified the same mutation in the son and father. Routine MRI showed pontine focal lesions in the eight-year-old son, though not in the father. We performed a four years follow-up study and at follow-up pontine hamartoma size remained unchanged in the son, and the father showed still no brain lesions, confirming thus an intra-familial phenotype variability.
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Thomas L, Spurlock G, Eudall C, Thomas NS, Mort M, Hamby SE, Chuzhanova N, Brems H, Legius E, Cooper DN, Upadhyaya M. Exploring the somatic NF1 mutational spectrum associated with NF1 cutaneous neurofibromas. Eur J Hum Genet 2011; 20:411-9. [PMID: 22108604 DOI: 10.1038/ejhg.2011.207] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Neurofibromatosis type-1 (NF1), caused by heterozygous inactivation of the NF1 tumour suppressor gene, is associated with the development of benign and malignant peripheral nerve sheath tumours (MPNSTs). Although numerous germline NF1 mutations have been identified, relatively few somatic NF1 mutations have been described in neurofibromas. Here we have screened 109 cutaneous neurofibromas, excised from 46 unrelated NF1 patients, for somatic NF1 mutations. NF1 mutation screening (involving loss-of-heterozygosity (LOH) analysis, multiplex ligation-dependent probe amplification and DNA sequencing) identified 77 somatic NF1 point mutations, of which 53 were novel. LOH spanning the NF1 gene region was evident in 25 neurofibromas, but in contrast to previous data from MPNSTs, it was absent at the TP53, CDKN2A and RB1 gene loci. Analysis of DNA/RNA from neurofibroma-derived Schwann cell cultures revealed NF1 mutations in four tumours whose presence had been overlooked in the tumour DNA. Bioinformatics analysis suggested that four of seven novel somatic NF1 missense mutations (p.A330T, p.Q519P, p.A776T, p.S1463F) could be of functional/clinical significance. Functional analysis confirmed this prediction for p.S1463F, located within the GTPase-activating protein-related domain, as this mutation resulted in a 150-fold increase in activated GTP-bound Ras. Comparison of the relative frequencies of the different types of somatic NF1 mutation observed with those of their previously reported germline counterparts revealed significant (P=0.001) differences. Although non-identical somatic mutations involving either the same or adjacent nucleotides were identified in three pairs of tumours from the same patients (P<0.0002), no association was noted between the type of germline and somatic NF1 lesion within the same individual.
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Affiliation(s)
- Laura Thomas
- Institute of Medical Genetics, School of Medicine, Cardiff University, Heath Park Way, Cardiff, UK
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Gabriele AL, Ruggieri M, Patitucci A, Magariello A, Conforti FL, Mazzei R, Muglia M, Ungaro C, Di Palma G, Citrigno L, Sproviero W, Gambardella A, Quattrone A. A novel NF1 gene mutation in an Italian family with neurofibromatosis type 1. Childs Nerv Syst 2011; 27:635-8. [PMID: 20927530 DOI: 10.1007/s00381-010-1282-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/05/2010] [Accepted: 09/09/2010] [Indexed: 11/26/2022]
Abstract
PURPOSE Neurofibromatosis type 1 (NF1) is a common autosomal dominant disorder with an estimated incidence of one in 3,500 births. Clinically, NF1 is characterized by café-au-lait (CAL) spots, neurofibromas, freckling of the axillary or inguinal region, Lisch nodules, optic nerve glioma, and bone dysplasias. NF1 is caused by inactivating mutations of the 17q11.2-located NF1 gene. We present a clinical and molecular study of an Italian family with NF1. METHODS The proband, a 10-year-old boy, showed large CAL spots and freckling on the axillary region and plexiform neurofibromas on the right side only. His father (47 years old) showed, in addition to the similar signs, numerous neurofibromas of various sizes on his thorax, abdomen, back, and shoulder. Two additional family members (a brother and a sister of the proband) presented only small CAL spots. The coding exons of NF1 gene were analyzed for mutations by denaturing high-performance liquid chromatography and sequencing in all family members. RESULTS The mutational analysis of the NF1 gene revealed a novel frameshift insertion mutation in exon 4c (c.654 ins A) in all affected family members. This novel mutation creates a shift on the reading frame starting at codon 218 and leads to the introduction of a premature stop at codon 227. CONCLUSIONS The segregation of the mutation with the affected phenotype and its absence in the 200 normal chromosomes suggest that it is responsible for the NF1 phenotype.
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Affiliation(s)
- Anna Lia Gabriele
- Institute of Neurological Science (ISN), National Research Council (CNR), Piano Lago di Mangone, Cosenza, Italy.
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Steinemann D, Arning L, Praulich I, Stuhrmann M, Hasle H, Stary J, Schlegelberger B, Niemeyer CM, Flotho C. Mitotic recombination and compound-heterozygous mutations are predominant NF1-inactivating mechanisms in children with juvenile myelomonocytic leukemia and neurofibromatosis type 1. Haematologica 2009; 95:320-3. [PMID: 20015894 DOI: 10.3324/haematol.2009.010355] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Children with neurofibromatosis type 1 (NF-1), being constitutionally deficient for one allele of the NF1 gene, are at greatly increased risk of juvenile myelomonocytic leukemia (JMML). NF1 is a negative regulator of RAS pathway activity, which has a central role in JMML. To further clarify the role of biallelic NF1 gene inactivation in the pathogenesis of JMML, we investigated the somatic NF1 lesion in 10 samples from children with JMML/NF-1. We report that two-thirds of somatic events involved loss of heterozygosity (LOH) at the NF1 locus, predominantly caused by segmental uniparental disomy of large parts of chromosome arm 17q. One-third of leukemias showed compound-heterozygous NF1-inactivating mutations. A minority of cases exhibited somatic interstitial deletions. The findings reinforce the emerging role of somatic mitotic recombination as a leukemogenic mechanism. In addition, they support the concept that biallelic NF1 inactivation in hematopoietic progenitor cells is required for transformation to JMML in children with NF-1.
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Affiliation(s)
- Doris Steinemann
- Cell and Molecular Pathology, Hannover Medical School, Hannover, Germany
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Ogasawara N, Sasaki M, Ishiguro H, Itoh Y, Nojiri S, Kubota E, Wada T, Kataoka H, Kuwabara Y, Joh T. Gastric schwannoma with adjacent external progression harbored aberrant NF2 gene. Dig Endosc 2009; 21:192-5. [PMID: 19691769 DOI: 10.1111/j.1443-1661.2009.00885.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Gastric schwannomas are rare benign mesenchymal tumors. We describe a schwannoma of gastric origin with adjacent external progression. Sections showed a spindle cell tumor arranged in interlaced bundles and fascicles that was S-100 and CD34 positive but c-KIT protein negative. Histology and immunohistochemistry revealed the typical appearance of a gastric schwannoma. Genetic evaluation revealed that the tumor harbored a point mutation in exon 6 of the tumor suppressor neurofibromatosis 2 (NF2) gene, which resulted in an amino acid substitution of NF2 protein, and no mutation in exon 4b of the NF1 gene. In conclusion, we identified a rare mutation of the NF2 gene in gastric schwannoma. A diagnosis can only be definitive when based on histological and immunohistochemical findings. Digestive tract schwannomas are rare mesenchymal tumors that are differentiated from gastrointestinal stromal tumors by the absence of KIT protein. Follow up suggested that complete resection is an effective long-term treatment strategy.
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Affiliation(s)
- Naotaka Ogasawara
- Department of Gastroenterology, Nagoya City University Graduate School of Medical Science, Mizuho-ku, Nagoya, Japan
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Brinckmann A, Mischung C, Bässmann I, Kühnisch J, Schuelke M, Tinschert S, Nürnberg P. Detection of novel NF1 mutations and rapid mutation prescreening with Pyrosequencing. Electrophoresis 2008; 28:4295-301. [PMID: 18041031 DOI: 10.1002/elps.200700118] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Neurofibromatosis type 1 (NF1) is caused by mutations in the neurofibromin (NF1) gene. Mutation analysis of NF1 is complicated by its large size, the lack of mutation hotspots, pseudogenes and frequent de novo mutations. Additionally, the search for NF1 mutations on the mRNA level is often hampered by nonsense-mediated mRNA decay (NMD) of the mutant allele. In this study we searched for mutations in a cohort of 38 patients and investigated the relationship between mutation type and allele-specific transcription from the wild-type versus mutant alleles. Quantification of relative mRNA transcript numbers was done by Pyrosequencing, a novel real-time sequencing method whose signals can be quantified very accurately. We identified 21 novel mutations comprising various mutation types. Pyrosequencing detected a definite relationship between allelic NF1 transcript imbalance due to NMD and mutation type in 24 of 29 patients who all carried frame-shift or nonsense mutations. NMD was absent in 5 patients with missense and silent mutations, as well as in 4 patients with splice-site mutations that did not disrupt the reading frame. Pyrosequencing was capable of detecting NMD even when the effects were only moderate. Diagnostic laboratories could thus exploit this effect for rapid prescreening for NF1 mutations as more than 60% of the mutations in this gene disrupt the reading frame and are prone to NMD.
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Affiliation(s)
- Anja Brinckmann
- Department of Neuropediatrics, Charité University Medical School, Berlin, Germany.
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12
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Neurofibromatosis: novel and recurrent mutations in Turkish patients. Pediatr Neurol 2007; 37:421-5. [PMID: 18021924 DOI: 10.1016/j.pediatrneurol.2007.07.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/12/2007] [Revised: 07/20/2007] [Accepted: 07/25/2007] [Indexed: 11/23/2022]
Abstract
Neurofibromatosis type 1 is an autosomal-dominant disorder affecting approximately 1 in 3500 births. It is characterized by café-au-lait spots, neurofibromas, axillary/inguinal freckling, and skeletal and neurologic signs. It exhibits full penetrance and a high mutation rate: 50% of neurofibromatosis type 1 patients represent a new mutation. The gene, located at 17q11.2, contains 60 exons that encode a 11-13-kb mRNA transcript. The mutation rate for neurofibromatosis type 1 is one of the highest known for human disorders, probably because of the large size of the gene, gene conversions mediated by pseudogenes, and the presence of repeated sequences. No clear genotype-phenotype correlation is established, except for patients with deletion of the entire neurofibromatosis type 1 gene. Neurofibromatosis type 1 mutations seem to be equally distributed along the gene. However, some exons in the neurofibromatosis type 1 gene may have a higher mutation rate, and the majority of these mutations are recurrent. We analyzed five exons (exons 4b, 16, 29, 31, and 37) for recurrent mutations and unknown mutations in 100 Turkish patients with neurofibromatosis type 1. We identified 496delGT and 499delTGTT mutations in exon 4b and 5866delA as a new mutation in exon 31 (Human Gene Mutation Database accession number Hd0524).
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13
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Griffiths S, Thompson P, Frayling I, Upadhyaya M. Molecular diagnosis of neurofibromatosis type 1: 2 years experience. Fam Cancer 2007; 6:21-34. [PMID: 16944272 DOI: 10.1007/s10689-006-9001-3] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2006] [Accepted: 07/11/2006] [Indexed: 11/30/2022]
Abstract
Our experience of providing an NF1 gene diagnostic mutation detection service as part of the U.K. Genetic Testing Network (UKGTN) is presented. A total of 169 unrelated individuals suspected of having neurofibromatosis type I (NF1) were referred for NF1 diagnostic testing over a 2 year period. Mutation analysis of the entire NF1 coding region and the flanking splice sites was carried out, and included the use of a combination of FISH, dHPLC and MLPA. Possible disease causing mutations were identified in 109 (64%) cases. These comprised 88 different sequence alterations, of which 57 were novel. Out of the 169 cases referred, there were 102 patients with reliable clinical data, of whom 78 satisfied the NIH diagnostic criteria for NF1. Within this better defined cohort of NF1 patients, NF1 mutations were identified in 61 individuals (78%), showing the importance of clinical selection on overall test sensitivity, and highlighting the problem of full clinical data collection in the audit of routine services. As mutation detection technologies advance, facilitating direct sequencing of all coding and flanking non-coding regions of the NF1 gene, the development of an even more cost-effective, quick and sensitive diagnostic test for future testing of NF1 is discussed.
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Affiliation(s)
- Siân Griffiths
- Institute of Medical Genetics, University Hospital of Wales, Cardiff CF14 4XN, UK
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14
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Henderson RA, Williamson K, Cumming S, Clarke MP, Lynch SA, Hanson IM, FitzPatrick DR, Sisodiya S, van Heyningen V. Inherited PAX6, NF1 and OTX2 mutations in a child with microphthalmia and aniridia. Eur J Hum Genet 2007; 15:898-901. [PMID: 17406642 DOI: 10.1038/sj.ejhg.5201826] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
A girl with aniridia, microphthalmia, microcephaly and café au lait macules was found to have mutations in PAX6, NF1 and OTX2. A novel PAX6 missense mutation (p.R38W) was inherited from her mother whose iris phenotype had not been evident because of ocular neurofibromatosis. Analysis of the NF1 gene in the proband, prompted by the mother's diagnosis and the presence of café au lait spots, revealed a nonsense mutation (p.R192X). Subsequently an OTX2 nonsense mutation (p.Y179X) was identified and shown to be inherited from her father who was initially diagnosed with Leber's congenital amaurosis. Since individual mutations in PAX6, OTX2 or NF1 can cause a variety of severe developmental defects, the proband's phenotype is surprisingly mild. This case shows that patients with complex phenotypes should not be eliminated from subsequent mutation analysis after one or even two mutations are found.
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Affiliation(s)
- R Alex Henderson
- Newcastle upon Tyne Hospitals NHS Trust, Newcastle upon Tyne, NE1 4LP, UK.
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15
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Oguzkan S, Terzi YK, Cinbis M, Anlar B, Aysun S, Ayter S. Molecular genetic analyses in neurofibromatosis type 1 patients with tumors. ACTA ACUST UNITED AC 2006; 165:167-71. [PMID: 16527612 DOI: 10.1016/j.cancergencyto.2005.08.029] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2005] [Revised: 08/25/2005] [Accepted: 08/29/2005] [Indexed: 12/13/2022]
Abstract
Neurofibromatosis type 1 (NF1) is one of the most common autosomal dominant disorders. NF1 is clinically characterized by neurofibromas, pigmentation anomalies, and an increased risk of malignant tumors. The NF1 gene product, neurofibromin, has a GTPase-activating protein domain (GRD) that interacts with the Ras protein, which is crucial in regulating signal transduction and cell proliferation/differentiation. We performed mutation analyses in the NF1-GRD region (exons 21-27a) and in exons 4b, 16, 29, and 37, and intron 28 in 17 NF1 patients with tumors. We identified a large deletion in the NF1 gene in a patient with a rhabdomyosarcoma as well as a variation in intron 22 in a patient with an optic glioma. We also found a 4-base pair deletion in another patient with optic glioma. In addition, allelic loss of the NF1 locus was shown in a pilocytic astrocytoma. Functional analyses of mutations in the NF1 gene may provide further insights into the pathogenesis of NF1 tumors.
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Affiliation(s)
- Sibel Oguzkan
- University of Hacettepe, Faculty of Medicine, Department of Medical Biology, 06100-Sihhiye, Ankara, Turkey
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16
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Lasota J, Wasag B, Dansonka-Mieszkowska A, Karcz D, Millward CL, Ryś J, Stachura J, Sobin LH, Miettinen M. Evaluation of NF2 and NF1 tumor suppressor genes in distinctive gastrointestinal nerve sheath tumors traditionally diagnosed as benign schwannomas: s study of 20 cases. J Transl Med 2003; 83:1361-71. [PMID: 13679444 DOI: 10.1097/01.lab.0000087591.29639.e3] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
A significant percentage of conventional schwannomas, whether sporadic or associated with neurofibromatosis 2 (NF2), show loss of heterozygosity (LOH) at NF2 and/or NF2 inactivating mutations. Similarly, a significant percentage of neurofibromas show LOH at NF1 and/or NF1 inactivating mutations. There are no molecular genetic data on gastrointestinal (GI) nerve sheath tumors traditionally diagnosed as benign schwannomas, rare neoplasms possibly derived from the schwannian elements dispersed between the smooth muscle fibers. In this study, we analyzed 1 esophageal, 16 gastric, 1 small intestinal, and 2 colonic tumors of such type. Histologically, all were spindle cell neoplasms positive for S-100 protein, vimentin, and glial fibrillary acidic protein, and negative for smooth muscle markers, KIT, CD34, neurofilament proteins, and HMB45. Focal or extensive lymphoid cuffs, often containing germinal centers, were present in most cases. None of the patients had NF2 or NF1. Chromosomes 22 and 17, particularly NF2 and NF1 loci, were analyzed for LOH in all GI tumors and for comparative purposes in 10 conventional schwannomas. LOH on 22q was seen in 40% of conventional schwannomas but in only 5% (1 of 20) of GI schwannomas. PCR amplification followed by direct sequencing of PCR products failed to identify mutations in NF2 coding sequences (exons 1-15) in 13 cases, including a case with LOH on 22q. Losses on 17q involving NF1 were seen in both GI and conventional schwannomas in 50% and 33% of analyzed tumors, respectively. LOH at NF1 might be one of the genetic features seen in peripheral nerve sheath tumors from different locations and should be interpreted with caution. However, lack of NF2 alterations strongly supports the hypothesis that GI schwannomas represent a morphologically and genetically distinct group of peripheral nerve sheath tumors that are different from conventional schwannomas.
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Affiliation(s)
- Jerzy Lasota
- Department of Soft Tissue Pathology, Armed Forces Institute of Pathology, Washington, DC 20306-600, USA.
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17
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Liu P, Xing W, Liang D, Huang G, Zhou Y, Cheng J. Fast Screening of Single-Nucleotide Polymorphisms Using Chip-Based Temperature Gradient Capillary Electrophoresis. ANAL LETT 2003. [DOI: 10.1081/al-120025258] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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18
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Abstract
Neurofibromatosis 1 is a progressive autosomal dominant condition caused by mutations in the NF1 gene on chromosome 17. The condition shows clinical variable expressivity, with varying features even between family members who share the same mutation. Furthermore, it is impossible to precisely predict the severity and course of the condition, a source of frustration for families and physicians. Neurofibromatosis 1 is also heterogeneous at the mutation level, with more than 300 independent mutations having been reported in this gene. The mutation data have accumulated slowly owing to the variability of the mutation types and the size and complexity of the gene. This is also reflected in the lack of a simple, inexpensive, highly accurate DNA-based test for neurofibromatosis 1 at present. This article reviews current NF1 mutation spectrum and testing, discussing and illustrating mutation mechanisms and pathogenetic effects, as well as factors affecting DNA testing and interpretation/diagnosis.
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Affiliation(s)
- Susanne A M Thomson
- Department of Molecular Genetics, University of Florida College of Medicine, Gainesville 32610-0266, USA
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19
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Perry A, Kunz SN, Fuller CE, Banerjee R, Marley EF, Liapis H, Watson MA, Gutmann DH. Differential NF1, p16, and EGFR patterns by interphase cytogenetics (FISH) in malignant peripheral nerve sheath tumor (MPNST) and morphologically similar spindle cell neoplasms. J Neuropathol Exp Neurol 2002; 61:702-9. [PMID: 12152785 DOI: 10.1093/jnen/61.8.702] [Citation(s) in RCA: 98] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Malignant peripheral nerve sheath tumors (MPNSTs) are diagnostically challenging neoplasms for which sensitive and specific immunohistochemical markers are lacking. Although limited to date, previous studies have suggested that NF1 (17q), NF2 (22q), p16 (9p), and EGFR (7p) alterations may be involved in MPNST tumorigenesis. To determine whether specific genetic changes differentiate between MPNST and morphologically similar neoplasms, we assessed these chromosomal regions in 22 MPNSTs (9 NF1-associated, 13 sporadic), 13 plexiform neurofibromas, 5 cellular schwannomas, 8 synovial sarcomas, 6 fibrosarcomas, and 13 hemangiopericytomas by 2-color FISH. NF1 deletions, often in the form of monosomy 17, were found in MPNSTs (76%). neurofibromas (31%), hemangiopericytomas (17%), and fibrosarcomas (17%), but not in synovial sarcomas or cellular schwannomas. NF1 losses were encountered more frequently in MPNSTs versus other sarcomas (p < 0.001), as were p16 homozygous deletions (45% vs 0%; p < 0.001), EGFR amplifications (26% vs 0%; p = 0.006), and polysomies for either chromosomes 7 (53% vs 12%; p = 0.003) or 22 (50% vs 4%; p < 0.001). Hemizygous or homozygous p16 deletions were detected in 75% of MPNSTs, but not in benign nerve sheath tumors (p < 0.001). Thus, FISH analysis identifies relatively specific genetic patterns that may be useful in selected cases, for which the differential diagnosis includes low- or high-grade MPNST.
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Affiliation(s)
- Arie Perry
- Department of Pathology, Washington University School of Medicine, St Louis, Missouri 63110-1093, USA
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20
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Tian H, Brody LC, Landers JP. Rapid detection of deletion, insertion, and substitution mutations via heteroduplex analysis using capillary- and microchip-based electrophoresis. Genome Res 2000; 10:1403-13. [PMID: 10984458 PMCID: PMC310899 DOI: 10.1101/gr.132700] [Citation(s) in RCA: 78] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
In this report, we explore the potential of capillary and microchip electrophoresis for heteroduplex analysis- (HDA) based mutation detection. Fluorescent dye-labeled primers (6-FAM-tagged) were used to amplify the DNA fragments ranging from 130 to 400 bp. The effects of DNA fragment length, matrix additives, pH, and salt were evaluated for capillary electrophoresis- (CE) and/or microchip electrophoresis-based HDA, using six heterozygous mutations, 185delAG, E1250X (3867GT), R1443G (4446CG), 5382insC, 5677insA in BRCA1, and 6174delT in BRCA2. For this system, the effective fragment size for CE-based HDA was found in the range of 200-300 bp, however, the effective range was 150-260 bp for microchip-based HDA. Sensitivity studies show CE-based HDA could detect a mutated DNA present at only 1%-10% of the total DNA. Discrimination between wild-type and deletion or insertion mutations in BRCA1 and BRCA2 with CE-based HDA could be achieved in <8 min, while the substitution mutations required 14 min of analysis time. For each mutation region, 15 samples were run to confirm the accuracy and reproducibility of the method. Using the method described, two previously reported mutations, E1038G (3232AG, missense) and 4427 C/T (4427CT, polymorphism), were detected in the tested samples and confirmed by DNA sequencing. Translation of the CE-based methodology to the microchip format allowed the analysis time for each mutation to be decreased to 130 sec. Based on the results obtained with this model system, it is possible that CE-based HDA methodologies can be developed and used effectively in genetic testing. The fast separation time and automated operation afforded with CE instrumentation provide a powerful system for screening mutations that include small deletions, insertions, and point mutations. Translation to the microchip platform, especially to a multichannel microchip system, would allow for screening mutations with high throughput.
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Affiliation(s)
- H Tian
- Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, USA
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21
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Fahsold R, Hoffmeyer S, Mischung C, Gille C, Ehlers C, Kücükceylan N, Abdel-Nour M, Gewies A, Peters H, Kaufmann D, Buske A, Tinschert S, Nürnberg P. Minor lesion mutational spectrum of the entire NF1 gene does not explain its high mutability but points to a functional domain upstream of the GAP-related domain. Am J Hum Genet 2000; 66:790-818. [PMID: 10712197 PMCID: PMC1288164 DOI: 10.1086/302809] [Citation(s) in RCA: 204] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/1999] [Accepted: 10/14/1999] [Indexed: 11/03/2022] Open
Abstract
More than 500 unrelated patients with neurofibromatosis type 1 (NF1) were screened for mutations in the NF1 gene. For each patient, the whole coding sequence and all splice sites were studied for aberrations, either by the protein truncation test (PTT), temperature-gradient gel electrophoresis (TGGE) of genomic PCR products, or, most often, by direct genomic sequencing (DGS) of all individual exons. A total of 301 sequence variants, including 278 bona fide pathogenic mutations, were identified. As many as 216 or 183 of the genuine mutations, comprising 179 or 161 different ones, can be considered novel when compared to the recent findings of Upadhyaya and Cooper, or to the NNFF mutation database. Mutation-detection efficiencies of the various screening methods were similar: 47.1% for PTT, 53.7% for TGGE, and 54.9% for DGS. Some 224 mutations (80.2%) yielded directly or indirectly premature termination codons. These mutations showed even distribution over the whole gene from exon 1 to exon 47. Of all sequence variants determined in our study, <20% represent C-->T or G-->A transitions within a CpG dinucleotide, and only six different mutations also occur in NF1 pseudogenes, with five being typical C-->T transitions in a CpG. Thus, neither frequent deamination of 5-methylcytosines nor interchromosomal gene conversion may account for the high mutation rate of the NF1 gene. As opposed to the truncating mutations, the 28 (10.1%) missense or single-amino-acid-deletion mutations identified clustered in two distinct regions, the GAP-related domain (GRD) and an upstream gene segment comprising exons 11-17. The latter forms a so-called cysteine/serine-rich domain with three cysteine pairs suggestive of ATP binding, as well as three potential cAMP-dependent protein kinase (PKA) recognition sites obviously phosphorylated by PKA. Coincidence of mutated amino acids and those conserved between human and Drosophila strongly suggest significant functional relevance of this region, with major roles played by exons 12a and 15 and part of exon 16.
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Affiliation(s)
- Raimund Fahsold
- Gemeinschaftspraxis B. Prager & A. Junge, Dresden; Epidauros AG, Bernried; Institut für Medizinische Genetik, Universitätsklinikum Charité, Berlin; Institut für Biochemie, Universitätsklinikum Charité, Berlin; Abteilung Humangenetik, Universität Ulm, Ulm
| | - Sven Hoffmeyer
- Gemeinschaftspraxis B. Prager & A. Junge, Dresden; Epidauros AG, Bernried; Institut für Medizinische Genetik, Universitätsklinikum Charité, Berlin; Institut für Biochemie, Universitätsklinikum Charité, Berlin; Abteilung Humangenetik, Universität Ulm, Ulm
| | - Claudia Mischung
- Gemeinschaftspraxis B. Prager & A. Junge, Dresden; Epidauros AG, Bernried; Institut für Medizinische Genetik, Universitätsklinikum Charité, Berlin; Institut für Biochemie, Universitätsklinikum Charité, Berlin; Abteilung Humangenetik, Universität Ulm, Ulm
| | - Christoph Gille
- Gemeinschaftspraxis B. Prager & A. Junge, Dresden; Epidauros AG, Bernried; Institut für Medizinische Genetik, Universitätsklinikum Charité, Berlin; Institut für Biochemie, Universitätsklinikum Charité, Berlin; Abteilung Humangenetik, Universität Ulm, Ulm
| | - Christian Ehlers
- Gemeinschaftspraxis B. Prager & A. Junge, Dresden; Epidauros AG, Bernried; Institut für Medizinische Genetik, Universitätsklinikum Charité, Berlin; Institut für Biochemie, Universitätsklinikum Charité, Berlin; Abteilung Humangenetik, Universität Ulm, Ulm
| | - Nazan Kücükceylan
- Gemeinschaftspraxis B. Prager & A. Junge, Dresden; Epidauros AG, Bernried; Institut für Medizinische Genetik, Universitätsklinikum Charité, Berlin; Institut für Biochemie, Universitätsklinikum Charité, Berlin; Abteilung Humangenetik, Universität Ulm, Ulm
| | - Maher Abdel-Nour
- Gemeinschaftspraxis B. Prager & A. Junge, Dresden; Epidauros AG, Bernried; Institut für Medizinische Genetik, Universitätsklinikum Charité, Berlin; Institut für Biochemie, Universitätsklinikum Charité, Berlin; Abteilung Humangenetik, Universität Ulm, Ulm
| | - Andreas Gewies
- Gemeinschaftspraxis B. Prager & A. Junge, Dresden; Epidauros AG, Bernried; Institut für Medizinische Genetik, Universitätsklinikum Charité, Berlin; Institut für Biochemie, Universitätsklinikum Charité, Berlin; Abteilung Humangenetik, Universität Ulm, Ulm
| | - Hartmut Peters
- Gemeinschaftspraxis B. Prager & A. Junge, Dresden; Epidauros AG, Bernried; Institut für Medizinische Genetik, Universitätsklinikum Charité, Berlin; Institut für Biochemie, Universitätsklinikum Charité, Berlin; Abteilung Humangenetik, Universität Ulm, Ulm
| | - Dieter Kaufmann
- Gemeinschaftspraxis B. Prager & A. Junge, Dresden; Epidauros AG, Bernried; Institut für Medizinische Genetik, Universitätsklinikum Charité, Berlin; Institut für Biochemie, Universitätsklinikum Charité, Berlin; Abteilung Humangenetik, Universität Ulm, Ulm
| | - Annegret Buske
- Gemeinschaftspraxis B. Prager & A. Junge, Dresden; Epidauros AG, Bernried; Institut für Medizinische Genetik, Universitätsklinikum Charité, Berlin; Institut für Biochemie, Universitätsklinikum Charité, Berlin; Abteilung Humangenetik, Universität Ulm, Ulm
| | - Sigrid Tinschert
- Gemeinschaftspraxis B. Prager & A. Junge, Dresden; Epidauros AG, Bernried; Institut für Medizinische Genetik, Universitätsklinikum Charité, Berlin; Institut für Biochemie, Universitätsklinikum Charité, Berlin; Abteilung Humangenetik, Universität Ulm, Ulm
| | - Peter Nürnberg
- Gemeinschaftspraxis B. Prager & A. Junge, Dresden; Epidauros AG, Bernried; Institut für Medizinische Genetik, Universitätsklinikum Charité, Berlin; Institut für Biochemie, Universitätsklinikum Charité, Berlin; Abteilung Humangenetik, Universität Ulm, Ulm
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