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Panier S, Wang S, Schumacher B. Genome Instability and DNA Repair in Somatic and Reproductive Aging. ANNUAL REVIEW OF PATHOLOGY 2024; 19:261-290. [PMID: 37832947 DOI: 10.1146/annurev-pathmechdis-051122-093128] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/15/2023]
Abstract
Genetic material is constantly subjected to genotoxic insults and is critically dependent on DNA repair. Genome maintenance mechanisms differ in somatic and germ cells as the soma only requires maintenance during an individual's lifespan, while the germline indefinitely perpetuates its genetic information. DNA lesions are recognized and repaired by mechanistically highly diverse repair machineries. The DNA damage response impinges on a vast array of homeostatic processes and can ultimately result in cell fate changes such as apoptosis or cellular senescence. DNA damage causally contributes to the aging process and aging-associated diseases, most prominently cancer. By causing mutations, DNA damage in germ cells can lead to genetic diseases and impact the evolutionary trajectory of a species. The mechanisms ensuring tight control of germline DNA repair could be highly instructive in defining strategies for improved somatic DNA repair. They may provide future interventions to maintain health and prevent disease during aging.
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Affiliation(s)
- Stephanie Panier
- Institute for Genome Stability in Aging and Disease and Cluster of Excellence: Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne and University Hospital of Cologne, Cologne, Germany;
- Max Planck Institute for Biology of Ageing, Cologne, Germany
| | - Siyao Wang
- Institute for Genome Stability in Aging and Disease and Cluster of Excellence: Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne and University Hospital of Cologne, Cologne, Germany;
- Center for Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany
- Institute of Molecular Biology (IMB), Mainz, Germany
| | - Björn Schumacher
- Institute for Genome Stability in Aging and Disease and Cluster of Excellence: Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne and University Hospital of Cologne, Cologne, Germany;
- Center for Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany
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2
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Zuntini R, Cattani C, Pedace L, Miele E, Caraffi SG, Gardini S, Ficarelli E, Pizzi S, Radio FC, Barone A, Piana S, Bertolini P, Corradi D, Marinelli M, Longo C, Motolese A, Zuffardi O, Tartaglia M, Garavelli L. Case Report: Sequential postzygotic HRAS mutation and gains of the paternal chromosome 11 carrying the mutated allele in a patient with epidermal nevus and rhabdomyosarcoma: evidence of a multiple-hit mechanism involving HRAS in oncogenic transformation. Front Genet 2023; 14:1231434. [PMID: 37636262 PMCID: PMC10447906 DOI: 10.3389/fgene.2023.1231434] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Accepted: 08/01/2023] [Indexed: 08/29/2023] Open
Abstract
We report a 7-year-old boy born with epidermal nevi (EN) arranged according to Blaschko's lines involving the face and head, right upper limb, chest, and left lower limb, who developed a left paratesticular embryonal rhabdomyosarcoma at 18 months of age. Parallel sequencing identified a gain-of-function variant (c.37G>C, p.Gly13Arg) of HRAS in both epidermal nevus and tumor but not in leukocytes or buccal mucosal epithelial cells, indicating its postzygotic origin. The variant accounted for 33% and 92% of the total reads in the nevus and tumor DNA specimens, respectively, supporting additional somatic hits in the latter. DNA methylation (DNAm) profiling of the tumor documented a signature consistent with embryonal rhabdomyosarcoma and CNV array analysis inferred from the DNAm arrays and subsequent MLPA analysis demonstrated copy number gains of the entire paternal chromosome 11 carrying the mutated HRAS allele, likely as the result of paternal unidisomy followed by subsequent gain(s) of the paternal chromosome in the tumor. Other structural rearrangements were observed in the tumours, while no additional pathogenic variants affecting genes with role in the RAS-MAPK and PI3K-AKT-MTOR pathways were identified. Our findings provide further evidence of the contribution of "gene dosage" to the multistep process driving cell transformation associated with hyperactive HRAS function.
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Affiliation(s)
- Roberta Zuntini
- Medical Genetics Unit, Azienda USL, IRCCS, Arcispedale Santa Maria Nuova, Reggio Emilia, Italy
| | - Chiara Cattani
- Medical Genetics Unit, Azienda USL, IRCCS, Arcispedale Santa Maria Nuova, Reggio Emilia, Italy
| | - Lucia Pedace
- Department of Pediatric Hematology, Oncology and Cellular and Gene Therapy, Ospedale Pediatrico Bambino Gesù, IRCCS, Rome, Italy
| | - Evelina Miele
- Department of Pediatric Hematology, Oncology and Cellular and Gene Therapy, Ospedale Pediatrico Bambino Gesù, IRCCS, Rome, Italy
| | | | - Stefano Gardini
- Dermatology Unit, Azienda USL, IRCCS, Arcispedale Santa Maria Nuova, Reggio Emilia, Italy
| | - Elena Ficarelli
- Dermatology Unit, Azienda USL, IRCCS, Arcispedale Santa Maria Nuova, Reggio Emilia, Italy
| | - Simone Pizzi
- Molecular Genetics and Functional Genomics Research Unit, Ospedale Pediatrico Bambino Gesù, IRCCS, Rome, Italy
| | - Francesca Clementina Radio
- Molecular Genetics and Functional Genomics Research Unit, Ospedale Pediatrico Bambino Gesù, IRCCS, Rome, Italy
| | - Angelica Barone
- Paediatric Hematology Oncology Unit, University Hospital of Parma, Parma, Italy
| | - Simonetta Piana
- Department of Oncology and Advanced Technologies, Pathology Unit, Azienda USL, IRCCS, Arcispedale S Maria Nuova, Reggio Emilia, Italy
| | - Patrizia Bertolini
- Paediatric Hematology Oncology Unit, University Hospital of Parma, Parma, Italy
| | - Domenico Corradi
- Department of Medicine and Surgery, Unit of Pathology, University of Parma, Parma, Italy
| | - Maria Marinelli
- Medical Genetics Unit, Azienda USL, IRCCS, Arcispedale Santa Maria Nuova, Reggio Emilia, Italy
| | - Caterina Longo
- Department of Dermatology, University of Modena and Reggio Emilia, Modena, Italy
- Department of Oncology and Advanced Technologies, Unit of Dermatology, Azienda USL, IRCCS, Arcispedale S Maria Nuova, Reggio Emilia, Italy
| | - Alberico Motolese
- Dermatology Unit, Azienda USL, IRCCS, Arcispedale Santa Maria Nuova, Reggio Emilia, Italy
| | - Orsetta Zuffardi
- Department of Molecular Medicine, University of Pavia, Pavia, Italy
| | - Marco Tartaglia
- Molecular Genetics and Functional Genomics Research Unit, Ospedale Pediatrico Bambino Gesù, IRCCS, Rome, Italy
| | - Livia Garavelli
- Medical Genetics Unit, Azienda USL, IRCCS, Arcispedale Santa Maria Nuova, Reggio Emilia, Italy
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Astiazaran-Symonds E, Ney GM, Higgs C, Oba L, Srivastava R, Livinski AA, Rosenberg PS, Stewart DR. Cancer in Costello syndrome: a systematic review and meta-analysis. Br J Cancer 2023; 128:2089-2096. [PMID: 36966234 PMCID: PMC10205753 DOI: 10.1038/s41416-023-02229-7] [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: 06/02/2022] [Revised: 02/22/2023] [Accepted: 03/02/2023] [Indexed: 03/27/2023] Open
Abstract
BACKGROUND Costello syndrome (CS) is a cancer-predisposition disorder caused by germline pathogenic variants in HRAS. We conducted a systematic review using case reports and case series to characterise cancer risk in CS. METHODS We conducted a systematic review to identify CS cases to create a retrospective cohort. We tested genotype-phenotype correlations and calculated cumulative incidence and hazard rates (HR) for cancer and cancer-free death, standardised incidence rates (SIR) and survival after cancer. RESULTS This study includes 234 publications reporting 621 patients from 35 countries. Over nine percent had cancer, including rhabdomyosarcoma, bladder, and neuroblastoma. The rate of cancer and death associated with p.Gly12Ser were lower when compared to all other variants (P < 0.05). Higher mortality for p.Gly12Cys, p.Gly12Asp, p.Gly12Val and p.Gly60Val and higher malignancy rate for p.Gly12Ala were confirmed (P < 0.05). Cumulative incidence by age 20 was 13% (cancer) and 11% (cancer-free death). HR (death) was 3-4% until age 3. Statistically significant SIRs were found for rhabdomyosarcoma (SIR = 1240), bladder (SIR = 1971), and neuroblastoma (SIR = 60). Survival after cancer appeared reduced. CONCLUSIONS This is the largest investigation of cancer in CS to date. The high incidence and SIR values found to highlight the need for rigorous surveillance and evidence-based guidelines for this high-risk population.
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Affiliation(s)
- Esteban Astiazaran-Symonds
- Clinical Genetics Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Rockville, MD, USA
- Department of Medicine, College of Medicine-Tucson, University of Arizona, Tucson, AZ, USA
| | - Gina M Ney
- Clinical Genetics Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Rockville, MD, USA
| | - Cecilia Higgs
- Clinical Genetics Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Rockville, MD, USA
| | - Leatrisse Oba
- Clinical Genetics Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Rockville, MD, USA
| | - Radhika Srivastava
- Clinical Genetics Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Rockville, MD, USA
| | - Alicia A Livinski
- NIH Library, Office of Research Services, Office of the Director, National Institutes of Health, Bethesda, MD, USA
| | - Philip S Rosenberg
- Biostatistics Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Rockville, MD, USA
| | - Douglas R Stewart
- Clinical Genetics Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Rockville, MD, USA.
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Metivier E, Prasad M, Prasad C. Neonatal hyperinsulinism-broadening the differential diagnosis. Paediatr Child Health 2023; 28:67-68. [PMID: 37151925 PMCID: PMC10156923 DOI: 10.1093/pch/pxac091] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2022] [Accepted: 08/04/2022] [Indexed: 12/23/2022] Open
Affiliation(s)
- Emma Metivier
- Western University Department of Pediatrics, London Health Sciences Centre, London, Ontario, Canada
| | - Madhavi Prasad
- Western University Department of Pediatrics, London Health Sciences Centre, London, Ontario, Canada
| | - Chitra Prasad
- Western University Department of Pediatrics, London Health Sciences Centre, London, Ontario, Canada
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Testicular germ cell tumors: Genomic alternations and RAS-dependent signaling. Crit Rev Oncol Hematol 2023; 183:103928. [PMID: 36717007 DOI: 10.1016/j.critrevonc.2023.103928] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Revised: 01/23/2023] [Accepted: 01/24/2023] [Indexed: 01/30/2023] Open
Abstract
Testicular germ cell tumors (TGCTs) are a common malignancy occurring in young adult men. The various genetic risk factors have been suggested to contribute to TGCT pathogenesis, however, they have a distinct mutational profile with a low rate of somatic point mutations, more frequent chromosomal gains, and aneuploidy. The most frequently mutated oncogenes in human cancers are RAS oncogenes, while their impact on testicular carcinogenesis and refractory disease is still poorly understood. In this mini-review, we summarize current knowledge on genetic alternations of RAS signaling-associated genes (the single nucleotide polymorphisms and point mutations) in this particular cancer type and highlight their link to chemotherapy resistance mechanisms. We also mention the impact of epigenetic changes on TGCT progression. Lastly, we propose a model for RAS-dependent signaling networks, regulation, cross-talks, and outcomes in TGCTs.
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Moreno-Del Val G, Muñoz-Robledano P, Caler AJ, Morante J. A method for multiple sampling mouse sperm in vivo†. Biol Reprod 2023; 108:197-203. [PMID: 36308433 DOI: 10.1093/biolre/ioac194] [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: 05/13/2022] [Revised: 09/15/2022] [Accepted: 10/20/2022] [Indexed: 11/12/2022] Open
Abstract
Mice are the most widely used animal model to study human diseases. However, the difficulty of in vivo recovery of mouse sperm has posed a limitation with its use in reproductive biology research. Several published techniques for obtaining sperm samples in vivo have been described, but most of them have several caveats. Critical limitations include poor reliability and significant mortality (Electroejaculation and drug-induced ejaculation), or the need for a large number of animals, careful programming, and laborious work (directed mating). Here, we describe a new approach for in vivo collection of sperm in the mouse via direct puncture of the epididymis to address these limitations. In addition, the technique is easy, safe, and reliable, allowing the animal to recover and maintain its fertility. In this way, punctual experiments could be carried out, or even more so, serial sampling of the same animal over time. Therefore, our approach allows for long-term and time-course experiments to study sperm characteristics under different treatments or conditions while maintaining the spermatogenic niche in vivo. In summary, we present our original approach as a powerful research tool to facilitate the study of spermatozoa relevant to various areas of biomedical research.
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Affiliation(s)
- Gonzalo Moreno-Del Val
- Instituto de Neurociencias, Consejo Superior de Investigaciones Cientificas (CSIC) and Universidad Miguel Hernández (UMH), San Juan de Alicante, Spain
| | - Patricia Muñoz-Robledano
- Instituto de Neurociencias, Consejo Superior de Investigaciones Cientificas (CSIC) and Universidad Miguel Hernández (UMH), San Juan de Alicante, Spain
| | - Antonio J Caler
- Instituto de Neurociencias, Consejo Superior de Investigaciones Cientificas (CSIC) and Universidad Miguel Hernández (UMH), San Juan de Alicante, Spain
| | - Javier Morante
- Instituto de Neurociencias, Consejo Superior de Investigaciones Cientificas (CSIC) and Universidad Miguel Hernández (UMH), San Juan de Alicante, Spain
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Eboreime J, Choi SK, Yoon SR, Sadybekov A, Katritch V, Calabrese P, Arnheim N. Germline selection of PTPN11 (HGNC:9644) variants make a major contribution to both Noonan syndrome's high birth rate and the transmission of sporadic cancer variants resulting in fetal abnormality. Hum Mutat 2022; 43:2205-2221. [PMID: 36349709 PMCID: PMC10099774 DOI: 10.1002/humu.24493] [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: 04/04/2022] [Revised: 09/20/2022] [Accepted: 10/12/2022] [Indexed: 11/10/2022]
Abstract
Some spontaneous germline gain-of-function mutations promote spermatogonial stem cell clonal expansion and disproportionate variant sperm production leading to unexpectedly high transmission rates for some human genetic conditions. To measure the frequency and spatial distribution of de novo mutations we divided three testes into 192 pieces each and used error-corrected deep-sequencing on each piece. We focused on PTPN11 (HGNC:9644) Exon 3 that contains 30 different PTPN11 Noonan syndrome (NS) mutation sites. We found 14 of these variants formed clusters among the testes; one testis had 11 different variant clusters. The mutation frequencies of these different clusters were not correlated with their case-recurrence rates nor were case recurrence rates of PTPN11 variants correlated with their tyrosine phosphatase levels thereby confusing PTPN11's role in germline clonal expansion. Six of the PTPN11 exon 3 de novo variants associated with somatic mutation-induced sporadic cancers (but not NS) also formed testis clusters. Further, three of these six variants were observed among fetuses that underwent prenatal ultrasound screening for NS-like features. Mathematical modeling showed that germline selection can explain both the mutation clusters and the high incidence of NS (1/1000-1/2500).
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Affiliation(s)
- Jordan Eboreime
- Department of Biological Sciences, Molecular and Computational Biology Program, University of Southern California, Los Angeles, California, USA
| | - Soo-Kyung Choi
- Department of Biological Sciences, Molecular and Computational Biology Program, University of Southern California, Los Angeles, California, USA
| | - Song-Ro Yoon
- Department of Biological Sciences, Molecular and Computational Biology Program, University of Southern California, Los Angeles, California, USA
| | - Anastasiia Sadybekov
- Department of Chemistry, Bridge Institute, University of Southern California, Los Angeles, California, USA
| | - Vsevolod Katritch
- Department of Chemistry, Bridge Institute, University of Southern California, Los Angeles, California, USA
| | - Peter Calabrese
- Department of Quantitative and Computational Biology, University of Southern California, Los Angeles, California, USA
| | - Norman Arnheim
- Department of Biological Sciences, Molecular and Computational Biology Program, University of Southern California, Los Angeles, California, USA
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Wood KA, Goriely A. The impact of paternal age on new mutations and disease in the next generation. Fertil Steril 2022; 118:1001-1012. [PMID: 36351856 PMCID: PMC10909733 DOI: 10.1016/j.fertnstert.2022.10.017] [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: 08/16/2022] [Revised: 10/09/2022] [Accepted: 10/11/2022] [Indexed: 11/09/2022]
Abstract
Advanced paternal age is associated with an increased risk of fathering children with genetic disorders and other adverse reproductive consequences. However, the mechanisms underlying this phenomenon remain largely unexplored. In this review, we focus on the impact of paternal age on de novo mutations that are an important contributor to genetic disease and can be studied both indirectly through large-scale sequencing studies and directly in the tissue in which they predominantly arise-the aging testis. We discuss the recent data that have helped establish the origins and frequency of de novo mutations, and highlight experimental evidence about the close link between new mutations, parental age, and genetic disease. We then focus on a small group of rare genetic conditions, the so-called "paternal age effect" disorders that show a strong association between paternal age and disease prevalence, and discuss the underlying mechanism ("selfish selection") and implications of this process in more detail. More broadly, understanding the causes and consequences of paternal age on genetic risk has important implications both for individual couples and for public health advice given that the average age of fatherhood is steadily increasing in many developed nations.
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Affiliation(s)
- Katherine A Wood
- Radcliffe Department of Medicine, MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, United Kingdom; National Institute for Health and Care Research (NIHR) Oxford Biomedical Research Centre, Oxford, United Kingdom
| | - Anne Goriely
- Radcliffe Department of Medicine, MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, United Kingdom; National Institute for Health and Care Research (NIHR) Oxford Biomedical Research Centre, Oxford, United Kingdom.
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Stevenson DA, Viscogliosi G, Leoni C. Bone health in RASopathies. AMERICAN JOURNAL OF MEDICAL GENETICS. PART C, SEMINARS IN MEDICAL GENETICS 2022; 190:459-470. [PMID: 36461161 DOI: 10.1002/ajmg.c.32020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Revised: 11/07/2022] [Accepted: 11/18/2022] [Indexed: 12/04/2022]
Abstract
The RASopathies are a group of disorders due to pathogenic variants in genes involved in the Ras/MAPK pathway, many of which have overlapping clinical features (e.g., neurofibromatosis type 1, Costello syndrome, cardiofaciocutaneous syndrome and Noonan syndrome) including musculoskeletal manifestations. Osteopenia and osteoporosis are reported in many of the RASopathies suggesting a shared pathogenesis. Even though osteopenia and osteoporosis are often detected and fractures have been reported, the clinical impact of bone mineralization defects on the skeleton of the various syndromes is poorly understood. Further knowledge of the role of the Ras/MAPK pathway on the bone cellular function, and more detailed musculoskeletal phenotyping will be critical in helping to develop therapies to improve bone health in the RASopathies.
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Affiliation(s)
- David A Stevenson
- Department of Pediatrics, Division of Medical Genetics, Stanford University, Stanford, California, USA
| | - Germana Viscogliosi
- Center for Rare Diseases and Birth Defect, Department of Woman and Child Health and Public Health, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy
| | - Chiara Leoni
- Center for Rare Diseases and Birth Defect, Department of Woman and Child Health and Public Health, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy
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Chaves Rabelo N, Gomes ME, de Oliveira Moraes I, Cantagalli Pfisterer J, Loss de Morais G, Antunes D, Caffarena ER, Llerena Jr J, Gonzalez S. RASopathy Cohort of Patients Enrolled in a Brazilian Reference Center for Rare Diseases: A Novel Familial LZTR1 Variant and Recurrent Mutations. Appl Clin Genet 2022; 15:153-170. [PMID: 36304179 PMCID: PMC9595068 DOI: 10.2147/tacg.s372761] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2022] [Accepted: 09/03/2022] [Indexed: 11/05/2022] Open
Abstract
Purpose Noonan syndrome and related disorders are genetic conditions affecting 1:1000-2000 individuals. Variants causing hyperactivation of the RAS/MAPK pathway lead to phenotypic overlap between syndromes, in addition to an increased risk of pediatric tumors. DNA sequencing methods have been optimized to provide a molecular diagnosis for clinical and genetic heterogeneity conditions. This work aimed to investigate the genetic basis in RASopathy patients through Next Generation Sequencing in a Reference Center for Rare Diseases (IFF/Fiocruz) and implement the precision medicine at a public health institute in Brazil. Patients and Methods This study comprises 26 cases with clinical suspicion of RASopathies. Sanger sequencing was used to screen variants in exons usually affected in the PTPN11 and HRAS genes for cases with clinical features of Noonan and Costello syndrome, respectively. Posteriorly, negative and new cases with clinical suspicion of RASopathy were analyzed by clinical or whole-exome sequencing. Results Molecular analysis revealed recurrent variants and a novel LZTR1 missense variant: 24 unrelated individuals with pathogenic variants [PTPN11(11), NF1(2), SOS1(2), SHOC2(2), HRAS(1), BRAF(1), LZTR (1), RAF1(1), KRAS(1), RIT1(1), a patient with co-occurrence of PTPN11 and NF1 mutations (1)]; familial cases carrying a known pathogenic variant in PTPN11 (mother-two children), and a previously undescribed paternally inherited variant in LZTR1. The comparative modeling analysis of the novel LZTR1 variant p.Pro225Leu showed local and global changes in the secondary and tertiary structures, showing a decrease of about 1% in the β-sheet content. Furthermore, evolutionary conservation indicated that Pro225 is in a highly conserved region, as observed for known dominant pathogenic variants in this protein. Conclusion Bringing precision medicine through NGS towards congenital syndromes promotes a better understanding of complex clinical and/or undiagnosed cases. The National Policy for Rare Diseases in Brazil emphasizes the importance of incorporating and optimizing diagnostic methodologies in the Unified Brazilian Health System (SUS). Therefore, this work is an important step for the NGS inclusion in diagnostic genetic routine in the public health system.
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Affiliation(s)
- Natana Chaves Rabelo
- Centro de Genética Médica IFF/Fiocruz, Rio de Janeiro, RJ, Brazil,Centro de Referência para Doenças Raras IFF/Fiocruz, Rio de Janeiro, RJ, Brazil,Laboratório de Medicina Genômica IFF/Fiocruz, Rio de Janeiro, RJ, Brazil
| | - Maria Eduarda Gomes
- Centro de Genética Médica IFF/Fiocruz, Rio de Janeiro, RJ, Brazil,Centro de Referência para Doenças Raras IFF/Fiocruz, Rio de Janeiro, RJ, Brazil,Laboratório de Medicina Genômica IFF/Fiocruz, Rio de Janeiro, RJ, Brazil
| | - Isabelle de Oliveira Moraes
- Centro de Genética Médica IFF/Fiocruz, Rio de Janeiro, RJ, Brazil,Centro de Referência para Doenças Raras IFF/Fiocruz, Rio de Janeiro, RJ, Brazil,Laboratório de Medicina Genômica IFF/Fiocruz, Rio de Janeiro, RJ, Brazil
| | - Juliana Cantagalli Pfisterer
- Centro de Genética Médica IFF/Fiocruz, Rio de Janeiro, RJ, Brazil,Centro de Referência para Doenças Raras IFF/Fiocruz, Rio de Janeiro, RJ, Brazil,Laboratório de Medicina Genômica IFF/Fiocruz, Rio de Janeiro, RJ, Brazil
| | | | - Deborah Antunes
- Laboratório de Genômica Funcional e Bioinformática, Instituto Oswaldo Cruz/Fiocruz, Rio de Janeiro, RJ, Brazil
| | - Ernesto Raúl Caffarena
- Grupo de Biofísica Computacional e Modelagem Molecular, Programa de Computação Científica, Fundação Oswaldo Cruz/Fiocruz, Rio de Janeiro, RJ, Brazil
| | - Juan Llerena Jr
- Centro de Genética Médica IFF/Fiocruz, Rio de Janeiro, RJ, Brazil,Centro de Referência para Doenças Raras IFF/Fiocruz, Rio de Janeiro, RJ, Brazil,Faculdade de Medicina de Petrópolis, FASE, Petrópolis, RJ, Brazil,INAGEMP, Rio de Janeiro, RJ, Brazil,Correspondence: Juan Llerena Jr, Email
| | - Sayonara Gonzalez
- Centro de Genética Médica IFF/Fiocruz, Rio de Janeiro, RJ, Brazil,Centro de Referência para Doenças Raras IFF/Fiocruz, Rio de Janeiro, RJ, Brazil,Laboratório de Medicina Genômica IFF/Fiocruz, Rio de Janeiro, RJ, Brazil
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Nandi S, Chennappan S, Andrasch Y, Fidan M, Engler M, Ahmad M, Tuckermann JP, Zenker M, Cirstea IC. Increased osteoclastogenesis contributes to bone loss in the Costello syndrome Hras G12V mouse model. Front Cell Dev Biol 2022; 10:1000575. [PMID: 36330334 PMCID: PMC9624175 DOI: 10.3389/fcell.2022.1000575] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Accepted: 09/29/2022] [Indexed: 11/16/2022] Open
Abstract
RAS GTPases are ubiquitous GDP/GTP-binding proteins that function as molecular switches in cellular signalling and control numerous signalling pathways and biological processes. Pathogenic mutations in RAS genes severely affect cellular homeostasis, leading to cancer when occurring in somatic cells and developmental disorders when the germline is affected. These disorders are generally termed as RASopathies and among them Costello syndrome (CS) is a distinctive entity that is caused by specific HRAS germline mutations. The majority of these mutations affect residues 12 and 13, the same sites as somatic oncogenic HRAS mutations. The hallmarks of the disease include congenital cardiac anomalies, impaired thriving and growth, neurocognitive impairments, distinctive craniofacial anomalies, and susceptibility to cancer. Adult patients often present signs of premature aging including reduced bone mineral density and osteoporosis. Using a CS mouse model harbouring a Hras G12V germline mutation, we aimed at determining whether this model recapitulates the patients’ bone phenotype and which bone cells are driving the phenotype when mutated. Our data revealed that Hras G12V mutation induces bone loss in mice at certain ages. In addition, we identified that bone loss correlated with an increased number of osteoclasts in vivo and Hras G12V mutations increased osteoclastogenesis in vitro. Last, but not least, mutant osteoclast differentiation was reduced by treatment in vitro with MEK and PI3K inhibitors, respectively. These results indicate that Hras is a novel regulator of bone homeostasis and an increased osteoclastogenesis due to Hras G12V mutation contributes to bone loss in the Costello syndrome.
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Affiliation(s)
- Sayantan Nandi
- Institute of Comparative Molecular Endocrinology, Ulm University, Ulm, Germany
| | | | - Yannik Andrasch
- Institute of Comparative Molecular Endocrinology, Ulm University, Ulm, Germany
| | - Miray Fidan
- Institute of Comparative Molecular Endocrinology, Ulm University, Ulm, Germany
| | - Melanie Engler
- Institute of Comparative Molecular Endocrinology, Ulm University, Ulm, Germany
| | - Mubashir Ahmad
- Institute of Comparative Molecular Endocrinology, Ulm University, Ulm, Germany
| | - Jan P. Tuckermann
- Institute of Comparative Molecular Endocrinology, Ulm University, Ulm, Germany
| | - Martin Zenker
- Institute of Human Genetics, University Hospital Magdeburg, Magdeburg, Germany
| | - Ion Cristian Cirstea
- Institute of Comparative Molecular Endocrinology, Ulm University, Ulm, Germany
- *Correspondence: Ion Cristian Cirstea,
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Ríos-González BE, Rodríguez-Ortiz JF, Castro-Martínez AG, Magaña-Torres MT, Barros-Núñez P. Clinical and molecular characterization of Costello syndrome in unrelated Mexican patients. Clin Dysmorphol 2022; 31:55-58. [PMID: 34845155 DOI: 10.1097/mcd.0000000000000405] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
This study intends to describe for the first time a cohort of Mexican patients with Costello syndrome. The five exons of the HRAS gene were amplified in DNA samples from 13 patients with a clinical suspicion of Costello syndrome. PCR products were sequenced using the Ready Reaction Big Dye Terminator v.3.0 Kit and an ABI PRISM 310 sequencer. Only five patients (38%) showed causal variant in codon 12 of the HRAS gene (four with the p.Gly12Ser and one with the p.Gly12Ala variant). Three patients showed silent polymorphic variants (p.His27His and p.Leu159Leu). Clinical features in patients carrying the causal variant were variable. The alternative diagnosis of cardio-facio-cutaneous syndrome was considered in patients who did not have a causative variant in HRAS.
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Affiliation(s)
| | | | - Anna G Castro-Martínez
- Genetic Department, Institute of Biological Sciences, Universidad Autónoma de Guadalajara
| | | | - Patricio Barros-Núñez
- Western Biomedical Research Center, IMSS
- Research Unit, Follow-up Metabolic Diseases, Pediatric UMAE, IMSS, Guadalajara, Mexico
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13
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Salazar R, Arbeithuber B, Ivankovic M, Heinzl M, Moura S, Hartl I, Mair T, Lahnsteiner A, Ebner T, Shebl O, Pröll J, Tiemann-Boege I. Discovery of an unusually high number of de novo mutations in sperm of older men using duplex sequencing. Genome Res 2022; 32:499-511. [PMID: 35210354 PMCID: PMC8896467 DOI: 10.1101/gr.275695.121] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Accepted: 01/14/2022] [Indexed: 11/25/2022]
Abstract
De novo mutations (DNMs) are important players in heritable diseases and evolution. Of particular interest are highly recurrent DNMs associated with congenital disorders that have been described as selfish mutations expanding in the male germline, thus becoming more frequent with age. Here, we have adapted duplex sequencing (DS), an ultradeep sequencing method that renders sequence information on both DNA strands; thus, one mutation can be reliably called in millions of sequenced bases. With DS, we examined ∼4.5 kb of the FGFR3 coding region in sperm DNA from older and younger donors. We identified sites with variant allele frequencies (VAFs) of 10-4 to 10-5, with an overall mutation frequency of the region of ∼6 × 10-7 Some of the substitutions are recurrent and are found at a higher VAF in older donors than in younger ones or are found exclusively in older donors. Also, older donors harbor more mutations associated with congenital disorders. Other mutations are present in both age groups, suggesting that these might result from a different mechanism (e.g., postzygotic mosaicism). We also observe that independent of age, the frequency and deleteriousness of the mutational spectra are more similar to COSMIC than to gnomAD variants. Our approach is an important strategy to identify mutations that could be associated with a gain of function of the receptor tyrosine kinase activity, with unexplored consequences in a society with delayed fatherhood.
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Affiliation(s)
- Renato Salazar
- Institute of Biophysics, Johannes Kepler University, Linz, Austria 4020
| | | | - Maja Ivankovic
- Institute of Biophysics, Johannes Kepler University, Linz, Austria 4020
| | - Monika Heinzl
- Institute of Biophysics, Johannes Kepler University, Linz, Austria 4020
| | - Sofia Moura
- Institute of Biophysics, Johannes Kepler University, Linz, Austria 4020
| | - Ingrid Hartl
- Institute of Biophysics, Johannes Kepler University, Linz, Austria 4020
| | - Theresa Mair
- Institute of Biophysics, Johannes Kepler University, Linz, Austria 4020
| | | | - Thomas Ebner
- Department of Gynecology, Obstetrics and Gynecological Endocrinology, Kepler University Hospital, Linz, Austria 4020
| | - Omar Shebl
- Department of Gynecology, Obstetrics and Gynecological Endocrinology, Kepler University Hospital, Linz, Austria 4020
| | - Johannes Pröll
- Center for Medical Research, Faculty of Medicine, Johannes Kepler University, Linz, Austria 4020
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14
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Aitken RJ. Role of sperm DNA damage in creating de novo mutations in human offspring: the ‘post-meiotic oocyte collusion’ hypothesis. Reprod Biomed Online 2022; 45:109-124. [DOI: 10.1016/j.rbmo.2022.03.012] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2021] [Revised: 03/10/2022] [Accepted: 03/11/2022] [Indexed: 11/24/2022]
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Abstract
The RASopathies are a group of disorders caused by a germline mutation in one of the genes encoding a component of the RAS/MAPK pathway. These disorders, including neurofibromatosis type 1, Noonan syndrome, cardiofaciocutaneous syndrome, Costello syndrome and Legius syndrome, among others, have overlapping clinical features due to RAS/MAPK dysfunction. Although several of the RASopathies are very rare, collectively, these disorders are relatively common. In this Review, we discuss the pathogenesis of the RASopathy-associated genetic variants and the knowledge gained about RAS/MAPK signaling that resulted from studying RASopathies. We also describe the cell and animal models of the RASopathies and explore emerging RASopathy genes. Preclinical and clinical experiences with targeted agents as therapeutics for RASopathies are also discussed. Finally, we review how the recently developed drugs targeting RAS/MAPK-driven malignancies, such as inhibitors of RAS activation, direct RAS inhibitors and RAS/MAPK pathway inhibitors, might be leveraged for patients with RASopathies.
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Affiliation(s)
- Katie E Hebron
- Pediatric Oncology Branch, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892, USA
| | - Edjay Ralph Hernandez
- Pediatric Oncology Branch, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892, USA
| | - Marielle E Yohe
- Pediatric Oncology Branch, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892, USA
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16
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A patient with severe congenital neutropenia harbors a missense ELANE mutation due to paternal germline mosaicism. Clin Chim Acta 2021; 526:14-20. [PMID: 34968504 DOI: 10.1016/j.cca.2021.12.023] [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: 10/05/2021] [Revised: 12/02/2021] [Accepted: 12/23/2021] [Indexed: 11/20/2022]
Abstract
BACKGROUND Clinical and genetic characteristics of ELANE mutation of a 3-year-old male who had a severe congenital neutropenia (SCN) were examined. We then investigated whether CRISPR/Cas9-mediated gene editing could correct the mutation. PROCEDURE The proband underwent extensive clinical assessments, such as exome sequencing and bioinformatics analysis, so that pathogenic genes could be identified. Sanger sequencing was also utilized for confirmation. The cell line, 293-ELANE, harboring ELANE mutation was generated, and the mutation was then corrected by CRISPR/Cas9-mediated homology-directed repair (HDR). RESULTS The ELANE gene test in the proband unveiled a heterozygous de novo missense mutation: c. 248T > A (p.V83D), which was not detected in his asymptomatic parents who had provided peripheral blood samples. We found that 46.01% of his father's sperm cells had the same mutation. These results demonstrate that the proband inherited the ELANE mutation from his father, who had an average neutrophil count but had a germline mosaicism. The highest repair efficiency of CRISPR/Cas9-mediated HDR for 293-ELANE is 4.43%. CONCLUSIONS We identified a missense mutation (p.V83D) in ELANE that causes SCN. This is the first report on paternal semen mosaicism of an ELANE mutation. Our study paves the way for preimplantation genetic diagnosis (PGD) based on ELANE mutation prevention and clinical treatment of congenital disabilities.
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17
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Abstract
[Figure: see text].
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Affiliation(s)
- Mitinori Saitou
- Institute for the Advanced Study of Human Biology (WPI-ASHBi), Kyoto University, Yoshida-Konoe-cho, Sakyo-ku, Kyoto 606-8501, Japan.,Department of Anatomy and Cell Biology, Graduate School of Medicine, Kyoto University, Yoshida-Konoe-cho, Sakyo-ku, Kyoto 606-8501, Japan.,Center for iPS Cell Research and Application (CiRA), Kyoto University, 53 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507, Japan
| | - Katsuhiko Hayashi
- Department of Developmental Stem Cell Biology, Faculty of Medical Sciences, Kyushu University, Maidashi 3-1-1, Higashi-ku, Fukuoka 812-8582, Japan.,Department of Germline Genetics, Graduate School of Medicine, Osaka University, 2-2 Yamada-oka, Suita, Osaka 565-0871, Japan
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18
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Breuss MW, Yang X, Gleeson JG. Sperm mosaicism: implications for genomic diversity and disease. Trends Genet 2021; 37:890-902. [PMID: 34158173 PMCID: PMC9484299 DOI: 10.1016/j.tig.2021.05.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Revised: 05/26/2021] [Accepted: 05/27/2021] [Indexed: 12/18/2022]
Abstract
While sperm mosaicism has few consequences for men, the offspring and future generations are unwitting recipients of gonadal cell mutations, often yielding severe disease. Recent studies, fueled by emergent technologies, show that sperm mosaicism is a common source of de novo mutations (DNMs) that underlie severe pediatric disease as well as human genetic diversity. Sperm mosaicism can be divided into three types: Type I arises during sperm meiosis and is non-age dependent; Type II arises in spermatogonia and increases as men age; and Type III arises during paternal embryogenesis, spreads throughout the body, and contributes stably to sperm throughout life. Where Types I and II confer little risk of recurrence, Type III may confer identifiable risk to future offspring. These mutations are likely to be the single largest contributor to human genetic diversity. New sequencing approaches may leverage this framework to evaluate and reduce disease risk for future generations.
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Affiliation(s)
- Martin W Breuss
- Department of Pediatrics, Section of Genetics and Metabolism, University of Colorado School of Medicine, Aurora, CO, USA
| | - Xiaoxu Yang
- Rady Children's Institute for Genomic Medicine, Department of Neurosciences, University of California, San Diego, CA, USA
| | - Joseph G Gleeson
- Rady Children's Institute for Genomic Medicine, Department of Neurosciences, University of California, San Diego, CA, USA.
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19
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Tiemann‐Boege I, Mair T, Yasari A, Zurovec M. Pathogenic postzygotic mosaicism in the tyrosine receptor kinase pathway: potential unidentified human disease hidden away in a few cells. FEBS J 2021; 288:3108-3119. [PMID: 32810928 PMCID: PMC8247027 DOI: 10.1111/febs.15528] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2020] [Revised: 07/17/2020] [Accepted: 08/14/2020] [Indexed: 01/19/2023]
Abstract
Mutations occurring during embryonic development affect only a subset of cells resulting in two or more distinct cell populations that are present at different levels, also known as postzygotic mosaicism (PZM). Although PZM is a common biological phenomenon, it is often overlooked as a source of disease due to the challenges associated with its detection and characterization, especially for very low-frequency variants. Moreover, PZM can cause a different phenotype compared to constitutional mutations. Especially, lethal mutations in receptor tyrosine kinase (RTK) pathway genes, which exist only in a mosaic state, can have completely new clinical manifestations and can look very different from the associated monogenic disorder. However, some key questions are still not addressed, such as the level of mosaicism resulting in a pathogenic phenotype and how the clinical outcome changes with the development and age. Addressing these questions is not trivial as we require methods with the sensitivity to capture some of these variants hidden away in very few cells. Recent ultra-accurate deep-sequencing approaches can now identify these low-level mosaics and will be central to understand systemic and local effects of mosaicism in the RTK pathway. The main focus of this review is to highlight the importance of low-level mosaics and the need to include their detection in studies of genomic variation associated with disease.
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Affiliation(s)
| | - Theresa Mair
- Institute of BiophysicsJohannes Kepler UniversityLinzAustria
| | - Atena Yasari
- Institute of BiophysicsJohannes Kepler UniversityLinzAustria
| | - Michal Zurovec
- Biology Centre of the Czech Academy of SciencesInstitute of EntomologyCeske BudejoviceCzech Republic
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20
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Vuralli D, Kosukcu C, Taskiran E, Simsek-Kiper PO, Utine GE, Boduroglu K, Alikasifoglu A, Alikasifoglu M. Hyperinsulinemic Hypoglycemia in a Patient with Costello Syndrome: An Etiology to Consider in Hypoglycemia. Mol Syndromol 2020; 11:207-216. [PMID: 33224014 DOI: 10.1159/000510171] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Accepted: 07/03/2020] [Indexed: 11/19/2022] Open
Abstract
Several endocrine disorders have been defined in patients with Costello syndrome (CS). In this report, we describe a patient with CS accompanied by a clinical picture of hyperinsulinemic hypoglycemia responsive to diazoxide treatment. A 41-day-old female patient with a birth weight of 3,600 g was referred for atypical facial features and swallowing dysfunction. She had a weight of 4,000 g (-0.8 SDS), a length of 50 cm (-2.4 SDS), and a head circumference of 38 cm (0.2 SDS). The clinical findings were suggestive of a genetic syndrome, mainly a RASopathy or Beckwith-Wiedemann syndrome. Whole exome sequencing revealed a de novo heterozygous missense variant in the HRAS (NM_001130442) gene in exon 2: c.35G>C; p.(Gly12Ala), establishing the molecular diagnosis of CS. The patient developed symptomatic hypoglycemia (jitteriness and sweating) at the age of 13 months. The patient's serum glucose was 38 mg/dL with simultaneous serum insulin and C-peptide levels, 2.8 μIU/mL and 1.8 ng/mL, respectively. Hyperinsulinism was suspected, and an exaggerated glucose response was detected in a glucagon test. Blood glucose monitoring indicated episodes of fasting hypoglycemia and postprandial hyperglycemia. Diazoxide of 10 mg/kg/day was initiated in 3 doses for hyperinsulinemic hypoglycemia, which resolved without new episodes of postprandial hyperglycemia. The patient deceased at the age of 17 months due to cardiorespiratory failure in the course of severe pneumonia complicated with pulmonary hypertension and hypertrophic cardiomyopathy. Several genetic syndromes including CS are associated with endocrinologic manifestations including abnormal glucose homeostasis. Although the frequency and underlying mechanisms leading to hyperinsulinemic hypoglycemia are yet unknown, hypoglycemia in CS responds well to diazoxide.
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Affiliation(s)
- Dogus Vuralli
- Division of Pediatric Endocrinology, Department of Pediatrics, Hacettepe University Medical School, Ankara, Turkey
| | - Can Kosukcu
- Department of Medical Genetics, Hacettepe University Medical School, Ankara, Turkey
| | - Ekim Taskiran
- Department of Medical Genetics, Hacettepe University Medical School, Ankara, Turkey
| | - Pelin Ozlem Simsek-Kiper
- Division of Pediatric Genetics, Department of Pediatrics, Hacettepe University Medical School, Ankara, Turkey
| | - Gulen Eda Utine
- Division of Pediatric Genetics, Department of Pediatrics, Hacettepe University Medical School, Ankara, Turkey
| | - Koray Boduroglu
- Division of Pediatric Genetics, Department of Pediatrics, Hacettepe University Medical School, Ankara, Turkey
| | - Ayfer Alikasifoglu
- Division of Pediatric Endocrinology, Department of Pediatrics, Hacettepe University Medical School, Ankara, Turkey
| | - Mehmet Alikasifoglu
- Department of Medical Genetics, Hacettepe University Medical School, Ankara, Turkey.,Division of Pediatric Genetics, Department of Pediatrics, Hacettepe University Medical School, Ankara, Turkey
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21
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Report From the International Society of Urological Pathology (ISUP) Consultation Conference on Molecular Pathology of Urogenital Cancers: IV: Current and Future Utilization of Molecular-Genetic Tests for Testicular Germ Cell Tumors. Am J Surg Pathol 2020; 44:e66-e79. [PMID: 32205480 PMCID: PMC7289140 DOI: 10.1097/pas.0000000000001465] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Supplemental Digital Content is available in the text. The International Society of Urological Pathology (ISUP) organized a Consultation Conference in March 2019 dealing with applications of molecular pathology in Urogenital Pathology, including testicular tumors (with a focus on germ cell tumors [GCTs]), preceded by a survey among its members to get insight into current practices in testicular germ cell tumor (TGCT) diagnostics and adoption of the ISUP immunohistochemical guidelines published in 2014. On the basis of the premeeting survey, the most commonly used immunomarker panel includes OCT3/4, placental alkaline phosphate, D2-40, SALL4, CD117, and CD30 for GCTs and the documentation of germ cell neoplasia in situ (GCNIS). Molecular testing, specifically 12p copy gain, is informative to distinguish non-GCNIS versus GCNIS related GCTs, and establishing germ cell origin of tumors both in the context of primary and metastatic lesions. Other molecular methodologies currently available but not widely utilized for TGCTs include genome-wide and targeted approaches for specific genetic anomalies, P53 mutations, genomic MDM2 amplification, and detection of the p53 inactivating miR-371a-3p. The latter also holds promise as a serum marker for malignant TGCTs. This manuscript provides an update on the classification of TGCTs, and describes the current and future role of molecular-genetic testing. The following recommendations are made: (1) Presence of GCNIS should be documented in all cases along with extent of spermatogenesis; (2) Immunohistochemical staining is optional in the following scenarios: identification of GCNIS, distinguishing embryonal carcinoma from seminoma, confirming presence of yolk sac tumor and/or choriocarcinoma, and differentiating spermatocytic tumor from potential mimics; (3) Detection of gain of the short arm of chromosome 12 is diagnostic to differentiate between non-GCNIS versus GCNIS related GCTs and supportive to the germ cell origin of both primary and metastatic tumors.
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22
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Maher GJ, Bernkopf M, Koelling N, Wilkie AOM, Meistrich ML, Goriely A. The impact of chemo- and radiotherapy treatments on selfish de novo FGFR2 mutations in sperm of cancer survivors. Hum Reprod 2020; 34:1404-1415. [PMID: 31348830 PMCID: PMC6688873 DOI: 10.1093/humrep/dez090] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2019] [Revised: 04/15/2019] [Indexed: 01/06/2023] Open
Abstract
STUDY QUESTION What effect does cancer treatment have on levels of spontaneous selfish fibroblast growth factor receptor 2 (FGFR2) point mutations in human sperm? SUMMARY ANSWER Chemotherapy and radiotherapy do not increase levels of spontaneous FGFR2 mutations in sperm but, unexpectedly, highly-sterilizing treatments dramatically reduce the levels of the disease-associated c.755C > G (Apert syndrome) mutation in sperm. WHAT IS KNOWN ALREADY Cancer treatments lead to short-term increases in gross DNA damage (chromosomal abnormalities and DNA fragmentation) but the long-term effects, particularly at the single nucleotide resolution level, are poorly understood. We have exploited an ultra-sensitive assay to directly quantify point mutation levels at the FGFR2 locus. STUDY DESIGN, SIZE, DURATION ‘Selfish’ mutations are disease-associated mutations that occur spontaneously in the sperm of most men and their levels typically increase with age. Levels of mutations at c.752–755 of FGFR2 (including c.755C > G and c.755C > T associated with Apert and Crouzon syndromes, respectively) in semen post-cancer treatment from 18 men were compared to levels in pre-treatment samples from the same individuals (n = 4) or levels in previously screened population controls (n = 99). PARTICIPANTS/MATERIALS, SETTING, METHODS Cancer patients were stratified into four different groups based on the treatments they received and the length of time for spermatogenesis recovery. DNA extracted from semen samples was analysed using a previously established highly sensitive assay to identify mutations at positions c.752–755 of FGFR2. Five to ten micrograms of semen genomic DNA was spiked with internal controls for quantification purposes, digested with MboI restriction enzyme and gel extracted. Following PCR amplification, further MboI digestion and a nested PCR with barcoding primers, samples were sequenced on Illumina MiSeq. Mutation levels were determined relative to the spiked internal control; in individuals heterozygous for a nearby common single nucleotide polymorphism (SNP), mutations were phased to their respective alleles. MAIN RESULTS AND THE ROLE OF CHANCE Patients treated with moderately-sterilizing alkylating regimens and who recovered spermatogenesis within <3 years after therapy (Group 3, n = 4) or non − alkylating chemotherapy and/or low gonadal radiation doses (Group 1, n = 4) had mutation levels similar to untreated controls. However, patients who had highly-sterilizing alkylating treatments (i.e. >5 years to spermatogenesis recovery) (Group 2, n = 7) or pelvic radiotherapy (Group 4, n = 3) exhibited c.755C > G mutation levels at or below background. Two patients (A and B) treated with highly-sterilizing alkylating agents demonstrated a clear reduction from pre-treatment levels; however pre-treatment samples were not available for the other patients with low mutation levels. Therefore, although based on their age we would expect detectable levels of mutations, we cannot exclude the possibility that these patients also had low mutation levels pre-treatment. In three patients with low c.755C > G levels at the first timepoint post-treatment, we observed increasing mutation levels over time. For two such patients we could phase the mutation to a nearby polymorphism (SNP) and determine that the mutation counts likely originated from a single or a small number of mutational events. LIMITATIONS, REASONS FOR CAUTION This study was limited to 18 patients with different treatment regimens; for nine of the 18 patients, samples from only one timepoint were available. Only 12 different de novo substitutions at the FGFR2 c.752–755 locus were assessed, two of which are known to be disease associated. WIDER IMPLICATIONS OF THE FINDINGS Our data add to the body of evidence from epidemiological studies and experimental data in humans suggesting that male germline stem cells are resilient to the accumulation of spontaneous mutations. Collectively, these data should provide physicians and health-care professionals with reassuring experimental-based evidence for counselling of male cancer patients contemplating their reproductive options several years after treatment. STUDY FUNDING/COMPETING INTEREST(S) This work was primarily supported by grants from the Wellcome (grant 091182 to AG and AOMW; grant 102 731 to AOMW), the University of Oxford Medical Sciences Division Internal Fund (grant 0005128 to GJM and AG), the National Institute for Health Research (NIHR) Oxford Biomedical Research Centre Programme (to AG) and the US National Institutes of Health (to MLM). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. None of the authors has any conflicts of interest to declare. TRIAL REGISTRATION NUMBER NA
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Affiliation(s)
- Geoffrey J Maher
- Clinical Genetics Group, MRC-Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK.,Nuffield Division of Clinical Laboratory Sciences, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Marie Bernkopf
- Clinical Genetics Group, MRC-Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK.,Nuffield Division of Clinical Laboratory Sciences, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Nils Koelling
- Clinical Genetics Group, MRC-Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK.,Nuffield Division of Clinical Laboratory Sciences, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Andrew O M Wilkie
- Clinical Genetics Group, MRC-Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK.,Nuffield Division of Clinical Laboratory Sciences, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Marvin L Meistrich
- Department of Experimental Radiation Oncology, University of Texas M.D. Anderson Cancer Center, Houston, USA
| | - Anne Goriely
- Clinical Genetics Group, MRC-Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK.,Nuffield Division of Clinical Laboratory Sciences, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
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23
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Dunnett-Kane V, Burkitt-Wright E, Blackhall FH, Malliri A, Evans DG, Lindsay CR. Germline and sporadic cancers driven by the RAS pathway: parallels and contrasts. Ann Oncol 2020; 31:873-883. [PMID: 32240795 PMCID: PMC7322396 DOI: 10.1016/j.annonc.2020.03.291] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Revised: 03/11/2020] [Accepted: 03/12/2020] [Indexed: 12/17/2022] Open
Abstract
Somatic mutations in RAS and related pathway genes such as NF1 have been strongly implicated in the development of cancer while also being implicated in a diverse group of developmental disorders named the 'RASopathies', including neurofibromatosis type 1 (NF1), Noonan syndrome (NS), Noonan syndrome with multiple lentigines (NSML), Costello syndrome (CS), cardiofaciocutaneous syndrome (CFC), and capillary malformation-arteriovenous syndrome (CM-AVM). It remains unclear why (i) there is little overlap in mutational subtype between Ras-driven malignancies associated with sporadic disease and those associated with the RASopathy syndromes, and (ii) RASopathy-associated cancers are usually of different histological origin to those seen with sporadic mutations of the same genes. For instance, germline variants in KRAS and NRAS are rarely found at codons 12, 13 or 61, the most common sites for somatic mutations in sporadic cancers. An exception is CS, where germline variants in codons 12 and 13 of HRAS occur relatively frequently. Given recent renewed drug interest following early clinical success of RAS G12C and farnesyl transferase inhibitors, an improved understanding of this relationship could help guide targeted therapies for both sporadic and germline cancers associated with the Ras pathway.
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Affiliation(s)
- V Dunnett-Kane
- Manchester University NHS Foundation Trust, Manchester, UK
| | - E Burkitt-Wright
- Manchester Centre for Genomic Medicine, Manchester University NHS Foundation Trust, Manchester, UK
| | - F H Blackhall
- Department of Medical Oncology, the Christie NHS Foundation Trust, Manchester, UK; Cancer Research UK Lung Cancer Centre of Excellence, London and Manchester, UK; Division of Molecular and Clinical Cancer Sciences, University of Manchester, Manchester, UK
| | - A Malliri
- Cancer Research UK Manchester Institute, University of Manchester, Manchester, UK
| | - D G Evans
- Manchester Centre for Genomic Medicine, Manchester University NHS Foundation Trust, Manchester, UK; Division of Evolution and Genomic Medicine, Faculty of Biology and Health, University of Manchester, Manchester, UK
| | - C R Lindsay
- Department of Medical Oncology, the Christie NHS Foundation Trust, Manchester, UK; Cancer Research UK Lung Cancer Centre of Excellence, London and Manchester, UK; Division of Molecular and Clinical Cancer Sciences, University of Manchester, Manchester, UK.
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24
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Predicting Gonadal Germ Cell Cancer in People with Disorders of Sex Development; Insights from Developmental Biology. Int J Mol Sci 2019; 20:ijms20205017. [PMID: 31658757 PMCID: PMC6834166 DOI: 10.3390/ijms20205017] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2019] [Revised: 10/03/2019] [Accepted: 10/05/2019] [Indexed: 01/03/2023] Open
Abstract
The risk of gonadal germ cell cancer (GGCC) is increased in selective subgroups, amongst others, defined patients with disorders of sex development (DSD). The increased risk is due to the presence of part of the Y chromosome, i.e., GonadoBlastoma on Y chromosome GBY region, as well as anatomical localization and degree of testicularization and maturation of the gonad. The latter specifically relates to the germ cells present being at risk when blocked in an embryonic stage of development. GGCC originates from either germ cell neoplasia in situ (testicular environment) or gonadoblastoma (ovarian-like environment). These precursors are characterized by presence of the markers OCT3/4 (POU5F1), SOX17, NANOG, as well as TSPY, and cKIT and its ligand KITLG. One of the aims is to stratify individuals with an increased risk based on other parameters than histological investigation of a gonadal biopsy. These might include evaluation of defined susceptibility alleles, as identified by Genome Wide Association Studies, and detailed evaluation of the molecular mechanism underlying the DSD in the individual patient, combined with DNA, mRNA, and microRNA profiling of liquid biopsies. This review will discuss the current opportunities as well as limitations of available knowledge in the context of predicting the risk of GGCC in individual patients.
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25
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Gripp KW, Morse LA, Axelrad M, Chatfield KC, Chidekel A, Dobyns W, Doyle D, Kerr B, Lin AE, Schwartz DD, Sibbles BJ, Siegel D, Shankar SP, Stevenson DA, Thacker MM, Weaver KN, White SM, Rauen KA. Costello syndrome: Clinical phenotype, genotype, and management guidelines. Am J Med Genet A 2019; 179:1725-1744. [PMID: 31222966 DOI: 10.1002/ajmg.a.61270] [Citation(s) in RCA: 65] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2019] [Revised: 05/22/2019] [Accepted: 06/01/2019] [Indexed: 12/16/2022]
Abstract
Costello syndrome (CS) is a RASopathy caused by activating germline mutations in HRAS. Due to ubiquitous HRAS gene expression, CS affects multiple organ systems and individuals are predisposed to cancer. Individuals with CS may have distinctive craniofacial features, cardiac anomalies, growth and developmental delays, as well as dermatological, orthopedic, ocular, and neurological issues; however, considerable overlap with other RASopathies exists. Medical evaluation requires an understanding of the multifaceted phenotype. Subspecialists may have limited experience in caring for these individuals because of the rarity of CS. Furthermore, the phenotypic presentation may vary with the underlying genotype. These guidelines were developed by an interdisciplinary team of experts in order to encourage timely health care practices and provide medical management guidelines for the primary and specialty care provider, as well as for the families and affected individuals across their lifespan. These guidelines are based on expert opinion and do not represent evidence-based guidelines due to the lack of data for this rare condition.
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Affiliation(s)
- Karen W Gripp
- Division of Medical Genetics, Department of Pediatrics, A.I. duPont Hospital for Children, Wilmington, Delaware
| | | | - Marni Axelrad
- Psychology Section, Department of Pediatrics, Baylor College of Medicine, Houston, Texas
| | - Kathryn C Chatfield
- Section of Cardiology, Department of Pediatrics, University of Colorado School of Medicine, Aurora, Colorado
| | - Aaron Chidekel
- Division of Pulmonology, Department of Pediatrics, A.I. duPont Hospital for Children, Wilmington, Delaware
| | - William Dobyns
- Division of Medical Genetics, Seattle Children's Hospital, Seattle, Washington
| | - Daniel Doyle
- Division of Endocrinology, A.I. duPont Hospital for Children, Wilmington, Delaware
| | - Bronwyn Kerr
- Manchester Center for Genomic Medicine, University of Manchester, Manchester, UK
| | - Angela E Lin
- Medical Genetics Unit, Department of Pediatrics, MassGeneral Hospital for Children, Boston, Massachusetts
| | - David D Schwartz
- Psychology Section, Department of Pediatrics, Baylor College of Medicine, Houston, Texas
| | - Barbara J Sibbles
- Division of Pediatrics, Erasmus MC-Sophia Children's Hospital, Rotterdam, the Netherlands
| | - Dawn Siegel
- Department of Dermatology, Medical College of Wisconsin, Milwaukee, Wisconsin
| | - Suma P Shankar
- Division of Genomic Medicine, Department of Pediatrics, University of California Davis, Sacramento, California
| | - David A Stevenson
- Division of Medical Genetic, Department of Pediatrics, Stanford University, Palo Alto, California
| | - Mihir M Thacker
- Department of Orthopedic Surgery, Nemoirs-Alfred I. duPont Hospital for Children, Wilmington, Delaware
| | - K Nicole Weaver
- Division of Human Genetics, University of Cincinnati College of Medicine, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
| | - Sue M White
- Victorian Clinical Genetics Services, Royal Children's Hospital, Victoria, Australia
| | - Katherine A Rauen
- Division of Genomic Medicine, Department of Pediatrics, University of California Davis, Sacramento, California
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Kuehne B, Heine E, Dafsari HS, Irwin R, Heller R, Bangen U, Brockmeier K, Kribs A, Oberthuer A, Cirak S. Use of whole exome sequencing in the NICU: Case of an extremely low birth weight infant with syndromic features. Mol Cell Probes 2019; 45:89-93. [DOI: 10.1016/j.mcp.2019.03.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2018] [Revised: 03/06/2019] [Accepted: 03/11/2019] [Indexed: 12/16/2022]
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Yamada M, Cai W, Martin LA, N’Tumba-Byn T, Seandel M. Functional robustness of adult spermatogonial stem cells after induction of hyperactive Hras. PLoS Genet 2019; 15:e1008139. [PMID: 31050682 PMCID: PMC6519842 DOI: 10.1371/journal.pgen.1008139] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2019] [Revised: 05/15/2019] [Accepted: 04/15/2019] [Indexed: 01/07/2023] Open
Abstract
Accumulating evidence indicates that paternal age correlates with disease risk in children. De novo gain-of-function mutations in the FGF-RAS-MAPK signaling pathway are known to cause a subset of genetic diseases associated with advanced paternal age, such as Apert syndrome, achondroplasia, Noonan syndrome, and Costello syndrome. It has been hypothesized that adult spermatogonial stem cells with pathogenic mutations are clonally expanded over time and propagate the mutations to offspring. However, no model system exists to interrogate mammalian germline stem cell competition in vivo. In this study, we created a lineage tracing system, which enabled undifferentiated spermatogonia with endogenous expression of HrasG12V, a known pathogenic gain-of-function mutation in RAS-MAPK signaling, to compete with their wild-type counterparts in the mouse testis. Over a year of fate analysis, neither HrasG12V-positive germ cells nor sperm exhibited a significant expansion compared to wild-type neighbors. Short-term stem cell capacity as measured by transplantation analysis was also comparable between wild-type and mutant groups. Furthermore, although constitutively active HRAS was detectable in the mutant cell lines, they did not exhibit a proliferative advantage or an enhanced response to agonist-evoked pERK signaling. These in vivo and in vitro results suggest that mouse spermatogonial stem cells are functionally resistant to a heterozygous HrasG12V mutation in the endogenous locus and that mechanisms could exist to prevent such harmful mutations from being expanded and transmitted to the next generation. Recent research has found that advanced paternal age is associated with increased risk in children to develop a subset of congenital anomalies, such as Apert syndrome, achondroplasia, Noonan syndrome, and Costello syndrome. The causative genetic errors (mutations) in these disorders have been identified to originate from the fathers’ testicles and their numbers increase with fathers’ age. It has been hypothesized that the germline stem cells that continuously self-renew and differentiate to supply sperm (referred as spermatogonial stem cells [SSCs]) carry these mutations and have the ability to expand preferentially as compared to normal SSCs with advancing age of the father, thereby increasing the likelihood of transmission of mutant sperm to the next generation. To test this hypothesis, we created a mouse model, in which a mutation known to enhance cell proliferation is induced in a subset of SSCs, and these cells compete with the neighboring normal (i.e., wild-type) stem cells. However, surprisingly, the germline cell population carrying the mutation in the testis was stable over a year of observation, suggesting that mechanisms could exist to prevent such harmful mutations from being expanded and transmitted to the next generation.
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Affiliation(s)
- Makiko Yamada
- Department of Surgery, Weill Cornell Medical College, New York, New York, United States of America
- * E-mail: (MY); (MS)
| | - Winson Cai
- Department of Surgery, Weill Cornell Medical College, New York, New York, United States of America
| | - Laura A. Martin
- Department of Surgery, Weill Cornell Medical College, New York, New York, United States of America
| | - Thierry N’Tumba-Byn
- Department of Surgery, Weill Cornell Medical College, New York, New York, United States of America
| | - Marco Seandel
- Department of Surgery, Weill Cornell Medical College, New York, New York, United States of America
- * E-mail: (MY); (MS)
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Cioppi F, Casamonti E, Krausz C. Age-Dependent De Novo Mutations During Spermatogenesis and Their Consequences. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1166:29-46. [DOI: 10.1007/978-3-030-21664-1_2] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Bustelo XR, Crespo P, Fernández-Pisonero I, Rodríguez-Fdez S. RAS GTPase-dependent pathways in developmental diseases: old guys, new lads, and current challenges. Curr Opin Cell Biol 2018; 55:42-51. [PMID: 30007125 PMCID: PMC7615762 DOI: 10.1016/j.ceb.2018.06.007] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2018] [Revised: 05/14/2018] [Accepted: 06/14/2018] [Indexed: 10/28/2022]
Abstract
Deregulated RAS signaling is associated with increasing numbers of congenital diseases usually referred to as RASopathies. The spectrum of genes and mutant alleles causing these diseases has been significantly expanded in recent years. This progress has triggered new challenges, including the origin and subsequent selection of the mutations driving these diseases, the specific pathobiological programs triggered by those mutations, the type of correlations that exist between the genotype and the clinical features of patients, and the ancillary genetic factors that influence the severity of the disease in patients. These issues also directly impinge on the feasibility of using RAS pathway drugs to treat RASopathy patients. Here, we will review the main developments and pending challenges in this research topic.
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Affiliation(s)
- Xosé R Bustelo
- Centro de Investigación del Cáncer, Consejo Superior de Investigaciones Científicas (CSIC)-University of Salamanca, 37007 Salamanca, Spain; Instituto de Biología Molecular y Celular del Cáncer, Consejo Superior de Investigaciones Científicas (CSIC)-University of Salamanca, 37007 Salamanca, Spain; Centro de Investigación Biomédica en Red de Cáncer (CIBERONC), Consejo Superior de Investigaciones Científicas (CSIC)-University of Salamanca, 37007 Salamanca, Spain.
| | - Piero Crespo
- CIBERONC, CSIC-University of Cantabria, 39011 Santander, Spain; Instituto de Biomedicina y Biotecnología de Cantabria, CSIC-University of Cantabria, 39011 Santander, Spain
| | - Isabel Fernández-Pisonero
- Centro de Investigación del Cáncer, Consejo Superior de Investigaciones Científicas (CSIC)-University of Salamanca, 37007 Salamanca, Spain; Instituto de Biología Molecular y Celular del Cáncer, Consejo Superior de Investigaciones Científicas (CSIC)-University of Salamanca, 37007 Salamanca, Spain; Centro de Investigación Biomédica en Red de Cáncer (CIBERONC), Consejo Superior de Investigaciones Científicas (CSIC)-University of Salamanca, 37007 Salamanca, Spain
| | - Sonia Rodríguez-Fdez
- Centro de Investigación del Cáncer, Consejo Superior de Investigaciones Científicas (CSIC)-University of Salamanca, 37007 Salamanca, Spain; Instituto de Biología Molecular y Celular del Cáncer, Consejo Superior de Investigaciones Científicas (CSIC)-University of Salamanca, 37007 Salamanca, Spain
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Genomic mosaicism in the pathogenesis and inheritance of a Rett syndrome cohort. Genet Med 2018; 21:1330-1338. [PMID: 30405208 PMCID: PMC6752670 DOI: 10.1038/s41436-018-0348-2] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2018] [Accepted: 10/17/2018] [Indexed: 01/01/2023] Open
Abstract
PURPOSE To determine the role of mosaicism in the pathogenesis and inheritance of Rett and Rett-like disorders. METHODS We recruited 471 Rett and Rett-like patients. Panel-sequencing targeting MECP2, CDKL5, and FOXG1 was performed. Mosaicism was quantified in 147 patients by a Bayesian genotyper. Candidates were validated by amplicon sequencing and digital PCR. Germline mosaicism of 21 fathers with daughters carrying pathogenic MECP2 variants was further quantified. RESULTS Pathogenic variants of MECP2/CDKL5/FOXG1 were found in 324/471 (68.7%) patients. Somatic MECP2 mosaicism was confirmed in 5/471 (1.1%) patients, including 3/18 males (16.7%) and 2/453 females (0.4%). Three of the five patients with somatic MECP2 mosaicism had mosaicism at MECP2-Arg106. Germline MECP2 mosaicism was detected in 5/21 (23.8%) fathers. CONCLUSION This is the first systematic screening of somatic and paternal germline MECP2 mosaicism at a cohort level. Our findings indicate that somatic MECP2 mosaicism contributes directly to the pathogenicity of Rett syndrome, especially in male patients. MECP2-Arg106 might be a mosaic hotspot. The high proportion of paternal germline MECP2 mosaicism indicates an underestimated mechanism underlying the paternal origin bias of MECP2 variants. Finally, this study provides an empirical foundation for future studies of genetic disorders caused by de novo variations of strong paternal origin.
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Maher GJ, Ralph HK, Ding Z, Koelling N, Mlcochova H, Giannoulatou E, Dhami P, Paul DS, Stricker SH, Beck S, McVean G, Wilkie AOM, Goriely A. Selfish mutations dysregulating RAS-MAPK signaling are pervasive in aged human testes. Genome Res 2018; 28:1779-1790. [PMID: 30355600 PMCID: PMC6280762 DOI: 10.1101/gr.239186.118] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2018] [Accepted: 10/20/2018] [Indexed: 02/07/2023]
Abstract
Mosaic mutations present in the germline have important implications for reproductive risk and disease transmission. We previously demonstrated a phenomenon occurring in the male germline, whereby specific mutations arising spontaneously in stem cells (spermatogonia) lead to clonal expansion, resulting in elevated mutation levels in sperm over time. This process, termed "selfish spermatogonial selection," explains the high spontaneous birth prevalence and strong paternal age-effect of disorders such as achondroplasia and Apert, Noonan and Costello syndromes, with direct experimental evidence currently available for specific positions of six genes (FGFR2, FGFR3, RET, PTPN11, HRAS, and KRAS). We present a discovery screen to identify novel mutations and genes showing evidence of positive selection in the male germline, by performing massively parallel simplex PCR using RainDance technology to interrogate mutational hotspots in 67 genes (51.5 kb in total) in 276 biopsies of testes from five men (median age, 83 yr). Following ultradeep sequencing (about 16,000×), development of a low-frequency variant prioritization strategy, and targeted validation, we identified 61 distinct variants present at frequencies as low as 0.06%, including 54 variants not previously directly associated with selfish selection. The majority (80%) of variants identified have previously been implicated in developmental disorders and/or oncogenesis and include mutations in six newly associated genes (BRAF, CBL, MAP2K1, MAP2K2, RAF1, and SOS1), all of which encode components of the RAS-MAPK pathway and activate signaling. Our findings extend the link between mutations dysregulating the RAS-MAPK pathway and selfish selection, and show that the aging male germline is a repository for such deleterious mutations.
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Affiliation(s)
- Geoffrey J Maher
- Clinical Genetics Group, MRC-Weatherall Institute of Molecular Medicine, University of Oxford, Oxford OX3 9DS, United Kingdom.,Nuffield Division of Clinical Laboratory Sciences, Radcliffe Department of Medicine, University of Oxford, Oxford OX3 9DS, United Kingdom
| | - Hannah K Ralph
- Clinical Genetics Group, MRC-Weatherall Institute of Molecular Medicine, University of Oxford, Oxford OX3 9DS, United Kingdom.,Nuffield Division of Clinical Laboratory Sciences, Radcliffe Department of Medicine, University of Oxford, Oxford OX3 9DS, United Kingdom
| | - Zhihao Ding
- Clinical Genetics Group, MRC-Weatherall Institute of Molecular Medicine, University of Oxford, Oxford OX3 9DS, United Kingdom.,Nuffield Division of Clinical Laboratory Sciences, Radcliffe Department of Medicine, University of Oxford, Oxford OX3 9DS, United Kingdom
| | - Nils Koelling
- Clinical Genetics Group, MRC-Weatherall Institute of Molecular Medicine, University of Oxford, Oxford OX3 9DS, United Kingdom.,Nuffield Division of Clinical Laboratory Sciences, Radcliffe Department of Medicine, University of Oxford, Oxford OX3 9DS, United Kingdom
| | - Hana Mlcochova
- Clinical Genetics Group, MRC-Weatherall Institute of Molecular Medicine, University of Oxford, Oxford OX3 9DS, United Kingdom.,Nuffield Division of Clinical Laboratory Sciences, Radcliffe Department of Medicine, University of Oxford, Oxford OX3 9DS, United Kingdom
| | - Eleni Giannoulatou
- Clinical Genetics Group, MRC-Weatherall Institute of Molecular Medicine, University of Oxford, Oxford OX3 9DS, United Kingdom.,Nuffield Division of Clinical Laboratory Sciences, Radcliffe Department of Medicine, University of Oxford, Oxford OX3 9DS, United Kingdom
| | - Pawan Dhami
- Medical Genomics, UCL Cancer Institute, University College London, London WC1E 6BT, United Kingdom
| | - Dirk S Paul
- Medical Genomics, UCL Cancer Institute, University College London, London WC1E 6BT, United Kingdom
| | - Stefan H Stricker
- Medical Genomics, UCL Cancer Institute, University College London, London WC1E 6BT, United Kingdom
| | - Stephan Beck
- Medical Genomics, UCL Cancer Institute, University College London, London WC1E 6BT, United Kingdom
| | - Gilean McVean
- Big Data Institute, Li Ka Shing Centre for Health Information and Discovery, University of Oxford, Oxford OX3 7LF, United Kingdom
| | - Andrew O M Wilkie
- Clinical Genetics Group, MRC-Weatherall Institute of Molecular Medicine, University of Oxford, Oxford OX3 9DS, United Kingdom.,Nuffield Division of Clinical Laboratory Sciences, Radcliffe Department of Medicine, University of Oxford, Oxford OX3 9DS, United Kingdom
| | - Anne Goriely
- Clinical Genetics Group, MRC-Weatherall Institute of Molecular Medicine, University of Oxford, Oxford OX3 9DS, United Kingdom.,Nuffield Division of Clinical Laboratory Sciences, Radcliffe Department of Medicine, University of Oxford, Oxford OX3 9DS, United Kingdom
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Abstract
Testicular cancer is the most common malignancy among men between 14 and 44 years of age, and its incidence has risen over the past two decades in Western countries. Both genetic and environmental factors contribute to the development of testicular cancer, for which cryptorchidism is the most common risk factor. Progress has been made in our understanding of the disease since the initial description of carcinoma in situ of the testis in 1972 (now referred to as germ cell neoplasia in situ), which has led to improved treatment options. The combination of surgery and cisplatin-based chemotherapy has resulted in a cure rate of >90% in patients with testicular cancer, although some patients become refractory to chemotherapy or have a late relapse; an improved understanding of the molecular determinants underlying tumour sensitivity and resistance may lead to the development of novel therapies for these patients. This Primer provides an overview of the biology, epidemiology, diagnosis and current treatment guidelines for testicular cancer, with a focus on germ cell tumours. We also outline areas for future research and what to expect in the next decade for testicular cancer.
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Hu P, Martinez AF, Kruszka P, Berger S, Roessler E, Muenke M. Low-level parental mosaicism affects the recurrence risk of holoprosencephaly. Genet Med 2018; 21:1015-1020. [DOI: 10.1038/s41436-018-0261-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2018] [Accepted: 07/26/2018] [Indexed: 11/09/2022] Open
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Goyal Y, Schüpbach T, Shvartsman SY. A quantitative model of developmental RTK signaling. Dev Biol 2018; 442:80-86. [PMID: 30026122 DOI: 10.1016/j.ydbio.2018.07.012] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2018] [Revised: 06/22/2018] [Accepted: 07/13/2018] [Indexed: 01/06/2023]
Abstract
Receptor tyrosine kinases (RTKs) control a wide range of developmental processes, from the first stages of embryogenesis to postnatal growth and neurocognitive development in the adult. A significant share of our knowledge about RTKs comes from genetic screens in model organisms, which provided numerous examples demonstrating how specific cell fates and morphologies are abolished when RTK activation is either abrogated or significantly reduced. Aberrant activation of such pathways has also been recognized in many forms of cancer. More recently, studies of human developmental syndromes established that excessive activation of RTKs and their downstream signaling effectors, most notably the Ras signaling pathway, can also lead to structural and functional defects. Given that both insufficient and excessive pathway activation can lead to abnormalities, mechanistic analysis of developmental RTK signaling must address quantitative questions about its regulation and function. Patterning events controlled by the RTK Torso in the early Drosophila embryo are well-suited for this purpose. This mini review summarizes current state of knowledge about Torso-dependent Ras activation and discusses its potential to serve as a quantitative model for studying the general principles of Ras signaling in development and disease.
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Affiliation(s)
- Yogesh Goyal
- Department of Chemical and Biological Engineering, Princeton University, Princeton, NJ 08544, United States; The Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ 08544, United States
| | - Trudi Schüpbach
- Department of Molecular Biology, Princeton University, Princeton, NJ 08544, United States
| | - Stanislav Y Shvartsman
- Department of Chemical and Biological Engineering, Princeton University, Princeton, NJ 08544, United States; The Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ 08544, United States; Department of Molecular Biology, Princeton University, Princeton, NJ 08544, United States.
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Genomic mosaicism in paternal sperm and multiple parental tissues in a Dravet syndrome cohort. Sci Rep 2017; 7:15677. [PMID: 29142202 PMCID: PMC5688122 DOI: 10.1038/s41598-017-15814-7] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2017] [Accepted: 11/02/2017] [Indexed: 12/21/2022] Open
Abstract
Genomic mosaicism in parental gametes and peripheral tissues is an important consideration for genetic counseling. We studied a Chinese cohort affected by a severe epileptic disorder, Dravet syndrome (DS). There were 56 fathers who donated semen and 15 parents who donated multiple peripheral tissue samples. We used an ultra-sensitive quantification method, micro-droplet digital PCR (mDDPCR), to detect parental mosaicism of the proband’s pathogenic mutation in SCN1A, the causal gene of DS in 112 families. Ten of the 56 paternal sperm samples were found to exhibit mosaicism of the proband’s mutations, with mutant allelic fractions (MAFs) ranging from 0.03% to 39.04%. MAFs in the mosaic fathers’ sperm were significantly higher than those in their blood (p = 0.00098), even after conditional probability correction (p’ = 0.033). In three mosaic fathers, ultra-low fractions of mosaicism (MAF < 1%) were detected in the sperm samples. In 44 of 45 cases, mosaicism was also observed in other parental peripheral tissues. Hierarchical clustering showed that MAFs measured in the paternal sperm, hair follicles and urine samples were clustered closest together. Milder epileptic phenotypes were more likely to be observed in mosaic parents (p = 3.006e-06). Our study provides new insights for genetic counseling.
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Wilkie AOM, Goriely A. Gonadal mosaicism and non-invasive prenatal diagnosis for 'reassurance' in sporadic paternal age effect (PAE) disorders. Prenat Diagn 2017; 37:946-948. [PMID: 28686291 PMCID: PMC5638092 DOI: 10.1002/pd.5108] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2017] [Revised: 06/25/2017] [Accepted: 07/01/2017] [Indexed: 12/20/2022]
Affiliation(s)
- Andrew O M Wilkie
- Clinical Genetics Group, Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
| | - Anne Goriely
- Clinical Genetics Group, Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
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Ultra-sensitive Sequencing Identifies High Prevalence of Clonal Hematopoiesis-Associated Mutations throughout Adult Life. Am J Hum Genet 2017; 101:50-64. [PMID: 28669404 DOI: 10.1016/j.ajhg.2017.05.013] [Citation(s) in RCA: 166] [Impact Index Per Article: 23.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2017] [Accepted: 05/18/2017] [Indexed: 12/13/2022] Open
Abstract
Clonal hematopoiesis results from somatic mutations in hematopoietic stem cells, which give an advantage to mutant cells, driving their clonal expansion and potentially leading to leukemia. The acquisition of clonal hematopoiesis-driver mutations (CHDMs) occurs with normal aging and these mutations have been detected in more than 10% of individuals ≥65 years. We aimed to examine the prevalence and characteristics of CHDMs throughout adult life. We developed a targeted re-sequencing assay combining high-throughput with ultra-high sensitivity based on single-molecule molecular inversion probes (smMIPs). Using smMIPs, we screened more than 100 loci for CHDMs in more than 2,000 blood DNA samples from population controls between 20 and 69 years of age. Loci screened included 40 regions known to drive clonal hematopoiesis when mutated and 64 novel candidate loci. We identified 224 somatic mutations throughout our cohort, of which 216 were coding mutations in known driver genes (DNMT3A, JAK2, GNAS, TET2, and ASXL1), including 196 point mutations and 20 indels. Our assay's improved sensitivity allowed us to detect mutations with variant allele frequencies as low as 0.001. CHDMs were identified in more than 20% of individuals 60 to 69 years of age and in 3% of individuals 20 to 29 years of age, approximately double the previously reported prevalence despite screening a limited set of loci. Our findings support the occurrence of clonal hematopoiesis-associated mutations as a widespread mechanism linked with aging, suggesting that mosaicism as a result of clonal evolution of cells harboring somatic mutations is a universal mechanism occurring at all ages in healthy humans.
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Giannoulatou E, Maher GJ, Ding Z, Gillis AJM, Dorssers LCJ, Hoischen A, Rajpert-De Meyts E, McVean G, Wilkie AOM, Looijenga LHJ, Goriely A. Whole-genome sequencing of spermatocytic tumors provides insights into the mutational processes operating in the male germline. PLoS One 2017; 12:e0178169. [PMID: 28542371 PMCID: PMC5439955 DOI: 10.1371/journal.pone.0178169] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2017] [Accepted: 05/08/2017] [Indexed: 12/31/2022] Open
Abstract
Adult male germline stem cells (spermatogonia) proliferate by mitosis and, after puberty, generate spermatocytes that undertake meiosis to produce haploid spermatozoa. Germ cells are under evolutionary constraint to curtail mutations and maintain genome integrity. Despite constant turnover, spermatogonia very rarely form tumors, so-called spermatocytic tumors (SpT). In line with the previous identification of FGFR3 and HRAS selfish mutations in a subset of cases, candidate gene screening of 29 SpTs identified an oncogenic NRAS mutation in two cases. To gain insights in the etiology of SpT and into properties of the male germline, we performed whole-genome sequencing of five tumors (4/5 with matched normal tissue). The acquired single nucleotide variant load was extremely low (~0.2 per Mb), with an average of 6 (2-9) non-synonymous variants per tumor, none of which is likely to be oncogenic. The observed mutational signature of SpTs is strikingly similar to that of germline de novo mutations, mostly involving C>T transitions with a significant enrichment in the ACG trinucleotide context. The tumors exhibited extensive aneuploidy (50-99 autosomes/tumor) involving whole-chromosomes, with recurrent gains of chr9 and chr20 and loss of chr7, suggesting that aneuploidy itself represents the initiating oncogenic event. We propose that SpT etiology recapitulates the unique properties of male germ cells; because of evolutionary constraints to maintain low point mutation rate, rare tumorigenic driver events are caused by a combination of gene imbalance mediated via whole-chromosome aneuploidy. Finally, we propose a general framework of male germ cell tumor pathology that accounts for their mutational landscape, timing and cellular origin.
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Affiliation(s)
- Eleni Giannoulatou
- Clinical Genetics Group, MRC-Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, United Kingdom
- Nuffield Division of Clinical Laboratory Sciences, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Geoffrey J. Maher
- Clinical Genetics Group, MRC-Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, United Kingdom
- Nuffield Division of Clinical Laboratory Sciences, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Zhihao Ding
- Clinical Genetics Group, MRC-Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, United Kingdom
- Nuffield Division of Clinical Laboratory Sciences, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Ad J. M. Gillis
- Department of Pathology, Erasmus MC—University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Lambert C. J. Dorssers
- Department of Pathology, Erasmus MC—University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Alexander Hoischen
- Department of Human Genetics, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Ewa Rajpert-De Meyts
- Department of Growth & Reproduction, Copenhagen University Hospital (Rigshospitalet), Copenhagen, Denmark
| | | | - Gilean McVean
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
| | - Andrew O. M. Wilkie
- Clinical Genetics Group, MRC-Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, United Kingdom
- Nuffield Division of Clinical Laboratory Sciences, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Leendert H. J. Looijenga
- Department of Pathology, Erasmus MC—University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Anne Goriely
- Clinical Genetics Group, MRC-Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, United Kingdom
- Nuffield Division of Clinical Laboratory Sciences, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
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Bertola D, Buscarilli M, Stabley DL, Baker L, Doyle D, Bartholomew DW, Sol-Church K, Gripp KW. Phenotypic spectrum of Costello syndrome individuals harboring the rare HRAS mutation p.Gly13Asp. Am J Med Genet A 2017; 173:1309-1318. [PMID: 28371260 DOI: 10.1002/ajmg.a.38178] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2016] [Revised: 12/12/2016] [Accepted: 01/18/2017] [Indexed: 12/19/2022]
Abstract
Costello syndrome is part of the RASopathies, a group of neurocardiofaciocutaneous syndromes caused by deregulation of the RAS mitogen-activated protein kinase pathway. Heterozygous mutations in HRAS are responsible for Costello syndrome, with more than 80% of the patients harboring the specific p.Gly12Ser variant. These individuals show a homogeneous phenotype. The clinical characteristics of the Costello syndrome individuals harboring rarer HRAS mutations are less understood, due to the small number of reported cases. Here, we describe the phenotypic spectrum of five additional individuals with HRAS c.38G>A; p.Gly13Asp, including one with somatic mosaicism, and review five previously described cases. The facial and hair abnormalities of the HRAS p.Gly13Asp individuals differ from the typical pattern observed in those showing the common HRAS (p.Gly12Ser) mutation, with less coarse facial features and slow growing, sparse hair with abnormal texture, the latter resembling the pattern observed in Noonan syndrome-like disorder with loose anagen hair and individuals harboring another amino acid substitution in HRAS (p.Gly13Cys). Although some individuals with HRAS p.Gly13Asp developed papillomata and vascular proliferation lesions, no malignant tumors occurred, similar to what was reported for individuals harboring the HRAS p.Gly13Cys. The fact that no malignant tumors were described in these individuals does not allow definitive conclusions about the risk for cancer development. It remains to be determined if substitutions of amino acid 13 in HRAS (p.Gly13Asp and p.Gly13Cys) increase the risk of tumor development.
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Affiliation(s)
- Débora Bertola
- Unidade de Genética Clínica, Instituto da Criança do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil.,Instituto de Biociências da Universidade de São Paulo, São Paulo, Brazil
| | - Michelle Buscarilli
- Unidade de Genética Clínica, Instituto da Criança do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil
| | - Deborah L Stabley
- Center for Applied Clinical Genomics, A. I. duPont Hospital for Children/Nemours, Wilmington, Delaware
| | - Laura Baker
- Division of Medical Genetics, A. I. duPont Hospital for Children/Nemours, Wilmington, Delaware
| | - Daniel Doyle
- Division of Endocrinology, A. I. duPont Hospital for Children/Nemours, Wilmington, Delaware
| | - Dennis W Bartholomew
- Division of Molecular and Human Genetics, Nationwide Children's Hospital, Columbus, Ohio
| | - Katia Sol-Church
- Center for Applied Clinical Genomics, A. I. duPont Hospital for Children/Nemours, Wilmington, Delaware
| | - Karen W Gripp
- Center for Applied Clinical Genomics, A. I. duPont Hospital for Children/Nemours, Wilmington, Delaware.,Division of Medical Genetics, A. I. duPont Hospital for Children/Nemours, Wilmington, Delaware
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40
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Acuna-Hidalgo R, Veltman JA, Hoischen A. New insights into the generation and role of de novo mutations in health and disease. Genome Biol 2016; 17:241. [PMID: 27894357 PMCID: PMC5125044 DOI: 10.1186/s13059-016-1110-1] [Citation(s) in RCA: 259] [Impact Index Per Article: 32.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Aside from inheriting half of the genome of each of our parents, we are born with a small number of novel mutations that occurred during gametogenesis and postzygotically. Recent genome and exome sequencing studies of parent-offspring trios have provided the first insights into the number and distribution of these de novo mutations in health and disease, pointing to risk factors that increase their number in the offspring. De novo mutations have been shown to be a major cause of severe early-onset genetic disorders such as intellectual disability, autism spectrum disorder, and other developmental diseases. In fact, the occurrence of novel mutations in each generation explains why these reproductively lethal disorders continue to occur in our population. Recent studies have also shown that de novo mutations are predominantly of paternal origin and that their number increases with advanced paternal age. Here, we review the recent literature on de novo mutations, covering their detection, biological characterization, and medical impact.
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Affiliation(s)
- Rocio Acuna-Hidalgo
- Department of Human Genetics, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Geert Grooteplein 10, 6525 GA, Nijmegen, The Netherlands
| | - Joris A Veltman
- Department of Human Genetics, Donders Institute of Neuroscience, Radboud University Medical Center, Geert Grooteplein 10, 6525 GA, Nijmegen, The Netherlands.
- Department of Clinical Genetics, GROW - School for Oncology and Developmental Biology, Maastricht University Medical Centre, Universiteitssingel 50, 6229 ER, Maastricht, The Netherlands.
| | - Alexander Hoischen
- Department of Human Genetics, Donders Institute of Neuroscience, Radboud University Medical Center, Geert Grooteplein 10, 6525 GA, Nijmegen, The Netherlands
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Yamada M, De Chiara L, Seandel M. Spermatogonial Stem Cells: Implications for Genetic Disorders and Prevention. Stem Cells Dev 2016; 25:1483-1494. [PMID: 27596369 PMCID: PMC5035912 DOI: 10.1089/scd.2016.0210] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Spermatogonial stem cells (SSCs) propagate mammalian spermatogenesis throughout male reproductive life by continuously self-renewing and differentiating, ultimately, into sperm. SSCs can be cultured for long periods and restore spermatogenesis upon transplantation back into the native microenvironment in vivo. Conventionally, SSC research has been focused mainly on male infertility and, to a lesser extent, on cell reprogramming. With the advent of genome-wide sequencing technology, however, human studies have uncovered a wide range of pathogenic alleles that arise in the male germ line. A subset of de novo point mutations was shown to originate in SSCs and cause congenital disorders in children. This review describes both monogenic diseases (eg, Apert syndrome) and complex disorders that are either known or suspected to be driven by mutations in SSCs. We propose that SSC culture is a suitable model for studying the origin and mechanisms of these diseases. Lastly, we discuss strategies for future clinical implementation of SSC-based technology, from detecting mutation burden by sperm screening to gene correction in vitro.
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Affiliation(s)
- Makiko Yamada
- Joan and Sanford I Weill Medical College of Cornell University, 12295, Surgery, New York, New York, United States ;
| | - Letizia De Chiara
- Joan and Sanford I Weill Medical College of Cornell University, 12295, Surgery, New York, New York, United States ;
| | - Marco Seandel
- Joan and Sanford I Weill Medical College of Cornell University, 12295, Surgery, New York, New York, United States ;
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42
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Whelan EC, Nwala AC, Osgood C, Olariu S. Selective mutation accumulation: a computational model of the paternal age effect. Bioinformatics 2016; 32:3790-3797. [PMID: 27531106 DOI: 10.1093/bioinformatics/btw528] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2016] [Revised: 07/12/2016] [Accepted: 08/09/2016] [Indexed: 11/14/2022] Open
Abstract
MOTIVATION As the mean age of parenthood grows, the effect of parental age on genetic disease and child health becomes ever more important. A number of autosomal dominant disorders show a dramatic paternal age effect due to selfish mutations: substitutions that grant spermatogonial stem cells (SSCs) a selective advantage in the testes of the father, but have a deleterious effect in offspring. In this paper we present a computational technique to model the SSC niche in order to examine the phenomenon and draw conclusions across different genes and disorders. RESULTS We used a Markov chain to model the probabilities of mutation and positive selection with cell divisions. The model was fitted to available data on disease incidence and also mutation assays of sperm donors. Strength of selective advantage is presented for a range of disorders including Apert's syndrome and achondroplasia. Incidence of the diseases was predicted closely for most disorders and was heavily influenced by the site-specific mutation rate and the number of mutable alleles. The model also successfully predicted a stronger selective advantage for more strongly activating gain-of-function mutations within the same gene. Both positive selection and the rate of copy-error mutations are important in adequately explaining the paternal age effect. AVAILABILITY AND IMPLEMENTATION C ++/R source codes and documentation including compilation instructions are available under GNU license at https://github.com/anwala/NicheSimulation CONTACT: ewhel001@odu.eduSupplementary information: Supplementary data are available at Bioinformatics online.
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Affiliation(s)
- Eoin C Whelan
- Department of Biology, Old Dominion University, Norfolk, VA, USA
| | - Alexander C Nwala
- Department of Computer Science, Old Dominion University, Norfolk, VA 23529, USA
| | | | - Stephan Olariu
- Department of Computer Science, Old Dominion University, Norfolk, VA 23529, USA
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43
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Abstract
Genome sequencing studies of de novo mutations in humans have revealed surprising incongruities in our understanding of human germline mutation. In particular, the mutation rate observed in modern humans is substantially lower than that estimated from calibration against the fossil record, and the paternal age effect in mutations transmitted to offspring is much weaker than expected from our long-standing model of spermatogenesis. I consider possible explanations for these discrepancies, including evolutionary changes in life-history parameters such as generation time and the age of puberty, a possible contribution from undetected post-zygotic mutations early in embryo development, and changes in cellular mutation processes at different stages of the germline. I suggest a revised model of stem-cell state transitions during spermatogenesis, in which 'dark' gonial stem cells play a more active role than hitherto envisaged, with a long cycle time undetected in experimental observations. More generally, I argue that the mutation rate and its evolution depend intimately on the structure of the germline in humans and other primates.This article is part of the themed issue 'Dating species divergences using rocks and clocks'.
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Affiliation(s)
- Aylwyn Scally
- Department of Genetics, University of Cambridge, Cambridge CB2 3EH, UK
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44
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Estimating Exceptionally Rare Germline and Somatic Mutation Frequencies via Next Generation Sequencing. PLoS One 2016; 11:e0158340. [PMID: 27341568 PMCID: PMC4920415 DOI: 10.1371/journal.pone.0158340] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2015] [Accepted: 06/14/2016] [Indexed: 11/22/2022] Open
Abstract
We used targeted next generation deep-sequencing (Safe Sequencing System) to measure ultra-rare de novo mutation frequencies in the human male germline by attaching a unique identifier code to each target DNA molecule. Segments from three different human genes (FGFR3, MECP2 and PTPN11) were studied. Regardless of the gene segment, the particular testis donor or the 73 different testis pieces used, the frequencies for any one of the six different mutation types were consistent. Averaging over the C>T/G>A and G>T/C>A mutation types the background mutation frequency was 2.6x10-5 per base pair, while for the four other mutation types the average background frequency was lower at 1.5x10-6 per base pair. These rates far exceed the well documented human genome average frequency per base pair (~10−8) suggesting a non-biological explanation for our data. By computational modeling and a new experimental procedure to distinguish between pre-mutagenic lesion base mismatches and a fully mutated base pair in the original DNA molecule, we argue that most of the base-dependent variation in background frequency is due to a mixture of deamination and oxidation during the first two PCR cycles. Finally, we looked at a previously studied disease mutation in the PTPN11 gene and could easily distinguish true mutations from the SSS background. We also discuss the limits and possibilities of this and other methods to measure exceptionally rare mutation frequencies, and we present calculations for other scientists seeking to design their own such experiments.
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45
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Hartung AM, Swensen J, Uriz IE, Lapin M, Kristjansdottir K, Petersen USS, Bang JMV, Guerra B, Andersen HS, Dobrowolski SF, Carey JC, Yu P, Vaughn C, Calhoun A, Larsen MR, Dyrskjøt L, Stevenson DA, Andresen BS. The Splicing Efficiency of Activating HRAS Mutations Can Determine Costello Syndrome Phenotype and Frequency in Cancer. PLoS Genet 2016; 12:e1006039. [PMID: 27195699 PMCID: PMC4873146 DOI: 10.1371/journal.pgen.1006039] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2016] [Accepted: 04/18/2016] [Indexed: 12/25/2022] Open
Abstract
Costello syndrome (CS) may be caused by activating mutations in codon 12/13 of the HRAS proto-oncogene. HRAS p.Gly12Val mutations have the highest transforming activity, are very frequent in cancers, but very rare in CS, where they are reported to cause a severe, early lethal, phenotype. We identified an unusual, new germline p.Gly12Val mutation, c.35_36GC>TG, in a 12-year-old boy with attenuated CS. Analysis of his HRAS cDNA showed high levels of exon 2 skipping. Using wild type and mutant HRAS minigenes, we confirmed that c.35_36GC>TG results in exon 2 skipping by simultaneously disrupting the function of a critical Exonic Splicing Enhancer (ESE) and creation of an Exonic Splicing Silencer (ESS). We show that this vulnerability of HRAS exon 2 is caused by a weak 3' splice site, which makes exon 2 inclusion dependent on binding of splicing stimulatory proteins, like SRSF2, to the critical ESE. Because the majority of cancer- and CS- causing mutations are located here, they affect splicing differently. Therefore, our results also demonstrate that the phenotype in CS and somatic cancers is not only determined by the different transforming potentials of mutant HRAS proteins, but also by the efficiency of exon 2 inclusion resulting from the different HRAS mutations. Finally, we show that a splice switching oligonucleotide (SSO) that blocks access to the critical ESE causes exon 2 skipping and halts proliferation of cancer cells. This unravels a potential for development of new anti-cancer therapies based on SSO-mediated HRAS exon 2 skipping.
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Affiliation(s)
- Anne-Mette Hartung
- Department of Biochemistry and Molecular Biology and The Villum Center for Bioanalytical Sciences, University of Southern Denmark, Odense M, Denmark
| | - Jeff Swensen
- Caris Life Sciences, Phoenix, Arizona, United States of America
- Department of Pathology, Children's Hospital of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
- ARUP Laboratories, Salt Lake City, Utah, United States of America
| | - Inaki E. Uriz
- Department of Biochemistry and Molecular Biology and The Villum Center for Bioanalytical Sciences, University of Southern Denmark, Odense M, Denmark
| | - Morten Lapin
- Department of Biochemistry and Molecular Biology and The Villum Center for Bioanalytical Sciences, University of Southern Denmark, Odense M, Denmark
| | - Karen Kristjansdottir
- Department of Biochemistry and Molecular Biology and The Villum Center for Bioanalytical Sciences, University of Southern Denmark, Odense M, Denmark
| | - Ulrika S. S. Petersen
- Department of Biochemistry and Molecular Biology and The Villum Center for Bioanalytical Sciences, University of Southern Denmark, Odense M, Denmark
| | - Jeanne Mari V. Bang
- Department of Biochemistry and Molecular Biology and The Villum Center for Bioanalytical Sciences, University of Southern Denmark, Odense M, Denmark
| | - Barbara Guerra
- Department of Biochemistry and Molecular Biology and The Villum Center for Bioanalytical Sciences, University of Southern Denmark, Odense M, Denmark
| | - Henriette Skovgaard Andersen
- Department of Biochemistry and Molecular Biology and The Villum Center for Bioanalytical Sciences, University of Southern Denmark, Odense M, Denmark
| | - Steven F. Dobrowolski
- Department of Pathology, Children's Hospital of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - John C. Carey
- Department of Pediatrics, University of Utah, Salt Lake City, Utah, United States of America
| | - Ping Yu
- ARUP Laboratories, Salt Lake City, Utah, United States of America
| | - Cecily Vaughn
- ARUP Laboratories, Salt Lake City, Utah, United States of America
| | - Amy Calhoun
- Department of Pediatrics, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Martin R. Larsen
- Department of Biochemistry and Molecular Biology and The Villum Center for Bioanalytical Sciences, University of Southern Denmark, Odense M, Denmark
| | - Lars Dyrskjøt
- Department of Molecular Medicine, Aarhus University Hospital, Aarhus, Denmark
| | - David A. Stevenson
- Division of Medical Genetics, Stanford University, Stanford, California, United States of America
| | - Brage S. Andresen
- Department of Biochemistry and Molecular Biology and The Villum Center for Bioanalytical Sciences, University of Southern Denmark, Odense M, Denmark
- * E-mail:
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46
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Arnheim N, Calabrese P. Germline Stem Cell Competition, Mutation Hot Spots, Genetic Disorders, and Older Fathers. Annu Rev Genomics Hum Genet 2016; 17:219-43. [PMID: 27070266 DOI: 10.1146/annurev-genom-083115-022656] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Some de novo human mutations arise at frequencies far exceeding the genome average mutation rate. Examples include the common mutations at one or a few sites in the genes that cause achondroplasia, Apert syndrome, multiple endocrine neoplasia type 2B, and Noonan syndrome. These mutations are recurrent, provide a gain of function, are paternally derived, and are more likely to be transmitted as the father ages. Recent experiments have tested whether the high mutation frequencies are due to an elevated mutation rate per cell division, as expected, or to an advantage of the mutant spermatogonial stem cells over wild-type stem cells. The evidence, which includes the surprising discovery of testis mutation clusters, rules out the former model but not the latter. We propose how the mutations might alter spermatogonial stem cell function and discuss how germline selection contributes to the paternal age effect, the human mutational load, and adaptive evolution.
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Affiliation(s)
- Norman Arnheim
- Molecular and Computational Biology Program, University of Southern California, Los Angeles, California 90089-2910; ,
| | - Peter Calabrese
- Molecular and Computational Biology Program, University of Southern California, Los Angeles, California 90089-2910; ,
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47
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Visualizing the origins of selfish de novo mutations in individual seminiferous tubules of human testes. Proc Natl Acad Sci U S A 2016; 113:2454-9. [PMID: 26858415 DOI: 10.1073/pnas.1521325113] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
De novo point mutations arise predominantly in the male germline and increase in frequency with age, but it has not previously been possible to locate specific, identifiable mutations directly within the seminiferous tubules of human testes. Using microdissection of tubules exhibiting altered expression of the spermatogonial markers MAGEA4, FGFR3, and phospho-AKT, whole genome amplification, and DNA sequencing, we establish an in situ strategy for discovery and analysis of pathogenic de novo mutations. In 14 testes from men aged 39-90 y, we identified 11 distinct gain-of-function mutations in five genes (fibroblast growth factor receptors FGFR2 and FGFR3, tyrosine phosphatase PTPN11, and RAS oncogene homologs HRAS and KRAS) from 16 of 22 tubules analyzed; all mutations have known associations with severe diseases, ranging from congenital or perinatal lethal disorders to somatically acquired cancers. These results support proposed selfish selection of spermatogonial mutations affecting growth factor receptor-RAS signaling, highlight its prevalence in older men, and enable direct visualization of the microscopic anatomy of elongated mutant clones.
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48
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Zhu W, Cooper DN, Zhao Q, Wang Y, Liu R, Li Q, Férec C, Wang Y, Chen JM. Concurrent nucleotide substitution mutations in the human genome are characterized by a significantly decreased transition/transversion ratio. Hum Mutat 2015; 36:333-41. [PMID: 25546635 DOI: 10.1002/humu.22749] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2014] [Accepted: 12/17/2014] [Indexed: 01/16/2023]
Abstract
There is accumulating evidence that the number of multiple-nucleotide substitutions (MNS) occurring in closely spaced sites in eukaryotic genomes is significantly higher than would be predicted from the random accumulation of independently generated single-nucleotide substitutions (SNS). Although this excess can in principle be accounted for by the concept of transient hypermutability, a general mutational signature of concurrent MNS mutations has not so far been evident. Employing a dataset (N = 449) of "concurrent" double MNS mutations causing human inherited disease, we have identified just such a mutational signature: concurrently generated double MNS mutations exhibit a >twofold lower transition/transversion ratio (termed RTs/Tv ) than independently generated de novo SNS mutations (<0.80 vs. 2.10; P = 2.69 × 10(-14) ). We replicated this novel finding through a similar analysis employing two double MNS variant datasets with differing abundances of concurrent events (150,521 variants with both substitutions on the same haplotypic lineage vs. 94,875 variants whose component substitutions were on different haplotypic lineages) plus 5,430,874 SNS variants, all being derived from the whole-genome sequencing of seven Chinese individuals. Evaluation of the newly observed mutational signature in diverse contexts provides solid support for the postulated role of translesion synthesis DNA polymerases in transient hypermutability.
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Affiliation(s)
- Wenjuan Zhu
- Beijing Genomics Institute (BGI)-Shenzhen, Shenzhen, China
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49
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Gripp KW, Robbins KM, Sheffield BS, Lee AF, Patel MS, Yip S, Doyle D, Stabley D, Sol-Church K. Paternal uniparental disomy 11p15.5 in the pancreatic nodule of an infant with Costello syndrome: Shared mechanism for hyperinsulinemic hypoglycemia in neonates with Costello and Beckwith-Wiedemann syndrome and somatic loss of heterozygosity in Costello syndrome driving clonal expansion. Am J Med Genet A 2015; 170:559-64. [PMID: 26572961 DOI: 10.1002/ajmg.a.37471] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2015] [Accepted: 11/01/2015] [Indexed: 11/09/2022]
Abstract
Costello syndrome (CS) entails a cancer predisposition and is caused by activating HRAS mutations, typically arising de novo in the paternal germline. Hypoglycemia is common in CS neonates. A previously reported individual with the rare HRAS p.Gln22Lys had hyperinsulinemic hypoglycemia. Autopsy showed a discrete pancreatic nodule. The morphologic and immunohistochemistry findings, including loss of p57(Kip2) protein, were identical to a focal lesion of congenital hyperinsulinism, however, no KCNJ11 or ABCC8 mutation was identified and germline derived DNA showed no alternation of the maternal or paternal 11p15 alleles. Here we report paternal uniparental disomy (pUPD) within the lesion, similar to the pUPD11p15.5 in Beckwith-Wiedemann syndrome (BWS). The similar extent of the pUPD suggests a similar mechanism driving hyperinsulinemia in both conditions. After coincidental somatic LOH and pUPD, the growth promoting effects of the paternally derived HRAS mutation, in combination with the increased function of the adjacent paternally expressed IGF2, may together result in clonal expansion. Although this somatic LOH within pancreatic tissue resulted in hyperinsulinism, similar LOH in mesenchymal cells may drive embryonal rhabdomyosarcoma (ERMS). Interestingly, biallelic IGF2 expression has been linked to rhabdomyosarcoma tumorigenesis and pUPD11 occurred in all 8 ERMS samples from CS individuals. Somatic KRAS and HRAS mutations occur with comparable frequency in isolated malignancies. Yet, the malignancy risk in CS is notably higher than in Noonan syndrome with a KRAS mutation. It is conceivable that HRAS co-localization with IGF2 and the combined effect of pUPD 11p15.5 on both genes contributes to the oncogenic potential.
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Affiliation(s)
- Karen W Gripp
- Division of Medical Genetics, A. I. du Pont Hospital for Children/Nemours, Wilmington, Delaware
| | - Katherine M Robbins
- Biomedical Research, A. I. du Pont Hospital for Children/Nemours, Wilmington, Delaware
| | | | - Anna F Lee
- Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada
| | - Millan S Patel
- Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada
| | - Stephen Yip
- Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada
| | - Daniel Doyle
- Division of Endocrinology, A. I. du Pont Hospital for Children/Nemours, Wilmington, Delaware
| | - Deborah Stabley
- Biomedical Research, A. I. du Pont Hospital for Children/Nemours, Wilmington, Delaware
| | - Katia Sol-Church
- Biomedical Research, A. I. du Pont Hospital for Children/Nemours, Wilmington, Delaware
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50
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Seplyarskiy VB, Bazykin GA, Soldatov RA. Polymerase ζ Activity Is Linked to Replication Timing in Humans: Evidence from Mutational Signatures. Mol Biol Evol 2015; 32:3158-72. [PMID: 26376651 DOI: 10.1093/molbev/msv184] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Replication timing is an important determinant of germline mutation patterns, with a higher rate of point mutations in late replicating regions. Mechanisms underlying this association remain elusive. One of the suggested explanations is the activity of error-prone DNA polymerases in late-replicating regions. Polymerase zeta (pol ζ), an essential error-prone polymerase biased toward transversions, also has a tendency to produce dinucleotide mutations (DNMs), complex mutational events that simultaneously affect two adjacent nucleotides. Experimental studies have shown that pol ζ is strongly biased toward GC→AA/TT DNMs. Using primate divergence data, we show that the GC→AA/TT pol ζ mutational signature is the most frequent among DNMs, and its rate exceeds the mean rate of other DNM types by a factor of approximately 10. Unlike the overall rate of DNMs, the pol ζ signature drastically increases with the replication time in the human genome. Finally, the pol ζ signature is enriched in transcribed regions, and there is a strong prevalence of GC→TT over GC→AA DNMs on the nontemplate strand, indicating association with transcription. A recurrently occurring GC→TT DNM in HRAS and SOD1 genes causes the Costello syndrome and amyotrophic lateral sclerosis correspondently; we observe an approximately 1 kb long mutation hotspot enriched by transversions near these DNMs in both cases, suggesting a link between these diseases and pol ζ activity. This study uncovers the genomic preferences of pol ζ, shedding light on a novel cause of mutational heterogeneity along the genome.
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Affiliation(s)
- Vladimir B Seplyarskiy
- Institute of Information Transmission Problems (Kharkevich Institute) of the Russian Academy of Sciences, Moscow, Russia Department of Bioengineering and Bioinformatics, Lomonosov Moscow State University, Moscow, Russia Pirogov Russian National Research Medical University, Moscow, Russia
| | - Georgii A Bazykin
- Institute of Information Transmission Problems (Kharkevich Institute) of the Russian Academy of Sciences, Moscow, Russia Department of Bioengineering and Bioinformatics, Lomonosov Moscow State University, Moscow, Russia Pirogov Russian National Research Medical University, Moscow, Russia
| | - Ruslan A Soldatov
- Institute of Information Transmission Problems (Kharkevich Institute) of the Russian Academy of Sciences, Moscow, Russia Department of Bioengineering and Bioinformatics, Lomonosov Moscow State University, Moscow, Russia
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