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van der Merwe NC, Buccimazza I, Rossouw B, Araujo M, Ntaita KS, Schoeman M, Vorster K, Napo K, Kotze MJ, Oosthuizen J. Clinical relevance of double heterozygosity revealed by next-generation sequencing of homologous recombination repair pathway genes in South African breast cancer patients. Breast Cancer Res Treat 2024; 207:331-342. [PMID: 38814507 PMCID: PMC11297091 DOI: 10.1007/s10549-024-07362-2] [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: 03/22/2024] [Accepted: 04/24/2024] [Indexed: 05/31/2024]
Abstract
PURPOSE Genetically predisposed breast cancer (BC) patients represent a minor but clinically meaningful subgroup of the disease, with 25% of all cases associated with actionable variants in BRCA1/2. Diagnostic implementation of next-generation sequencing (NGS) resulted in the rare identification of BC patients with double heterozygosity for deleterious variants in genes partaking in homologous recombination repair of DNA. As clinical heterogeneity poses challenges for genetic counseling, this study focused on the occurrence and clinical relevance of double heterozygous BC in South Africa. METHODS DNA samples were diagnostically screened using the NGS-based Oncomine™ BRCA Expanded Research Assay. Data was generated on the Ion GeneStudio S5 system and analyzed using the Torrent Suite™ and reporter software. The clinical significance of the variants detected was determined using international variant classification guidelines and treatment implications. RESULTS Six of 1600 BC patients (0.375%) tested were identified as being bi-allelic for two germline likely pathogenic or pathogenic variants. Most of the variants were present in BRCA1/2, including two founder-related small deletions in three cases, with family-specific variants detected in ATM, BARD1, FANCD2, NBN, and TP53. The scientific interpretation and clinical relevance were based on the clinical and tumor characteristics of each case. CONCLUSION This study increased current knowledge of the risk implications associated with the co-occurrence of more than one pathogenic variant in the BC susceptibility genes, confirmed to be a rare condition in South Africa. Further molecular pathology-based studies are warranted to determine whether clinical decision-making is affected by the detection of a second pathogenic variant in BRCA1/2 and TP53 carriers.
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Affiliation(s)
- Nerina C van der Merwe
- Division of Human Genetics, Faculty of Health Sciences, University of the Free State, Bloemfontein, South Africa.
- Division of Human Genetics, National Health Laboratory Service, Universitas Hospital, Bloemfontein, South Africa.
| | - Ines Buccimazza
- Genetics Unit, Inkosi Albert Luthuli General Hospital, Durban, South Africa
- Department of Surgery, Nelson R Mandela School of Medicine, Inkosi Albert Luthuli General Hospital, Durban, South Africa
| | - Bianca Rossouw
- Division of Human Genetics, National Health Laboratory Service, Braamfontein, Johannesburg, South Africa
- Division of Human Genetics, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Monica Araujo
- Division of Human Genetics, National Health Laboratory Service, Braamfontein, Johannesburg, South Africa
- Division of Human Genetics, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Kholiwe S Ntaita
- Division of Human Genetics, Faculty of Health Sciences, University of the Free State, Bloemfontein, South Africa
- Division of Human Genetics, National Health Laboratory Service, Universitas Hospital, Bloemfontein, South Africa
| | - Mardelle Schoeman
- Division of Molecular Biology and Human Genetics, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa
| | - Karin Vorster
- Department of Oncology, Free State Department of Health, Universitas Annex Hospital, Bloemfontein, South Africa
- Department of Oncology, Faculty of Health Science, University of the Free State, Bloemfontein, South Africa
| | - Kgabo Napo
- Department of Oncology, Free State Department of Health, Universitas Annex Hospital, Bloemfontein, South Africa
- Department of Oncology, Faculty of Health Science, University of the Free State, Bloemfontein, South Africa
| | - Maritha J Kotze
- Division of Chemical Pathology, Department of Pathology, National Health Laboratory Service, Tygerberg Hospital, Cape Town, South Africa
- Division of Chemical Pathology, Department of Pathology, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa
| | - Jaco Oosthuizen
- Division of Human Genetics, Faculty of Health Sciences, University of the Free State, Bloemfontein, South Africa
- Division of Human Genetics, National Health Laboratory Service, Universitas Hospital, Bloemfontein, South Africa
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Ganatra H, Tan JK, Simmons A, Bigogno CM, Khurana V, Ghose A, Ghosh A, Mahajan I, Boussios S, Maniam A, Ayodele O. Applying whole-genome and whole-exome sequencing in breast cancer: a review of the landscape. Breast Cancer 2024:10.1007/s12282-024-01628-9. [PMID: 39190283 DOI: 10.1007/s12282-024-01628-9] [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: 03/15/2024] [Accepted: 08/19/2024] [Indexed: 08/28/2024]
Abstract
Whole-genome sequencing (WGS) and whole-exome sequencing (WES) are crucial within the context of breast cancer (BC) research. They play a role in the detection of predisposed genes, risk stratification, and identification of rare single nucleotide polymorphisms (SNPs). These technologies aid in the discovery of associations between various syndromes and BC, understanding the tumour microenvironment (TME), and even identifying unknown mutations that could be useful in future for personalised treatments. Genetic analysis can find the associated risk of BC and can be used in early screening, diagnosis, specific treatment plans, and prevention in patients who are at high risk of tumour formation. This article focuses on the application of WES and WGS, and how uncovering novel candidate genes associated with BC can aid in treating and preventing BC.
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Affiliation(s)
- Hetvi Ganatra
- Barts Cancer Institute, Cancer Research UK City of London, Queen Mary University of London, London, UK
| | - Joecelyn Kirani Tan
- School of Medicine, University of St. Andrews, Fife, Scotland, UK
- Andrews Oncology Society, Scotland, UK
| | - Ana Simmons
- Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
| | - Carola Maria Bigogno
- Department of Medical Oncology, Barts Cancer Centre, St Bartholomew's Hospital, Barts Health NHS Trust, London, UK
- British Oncology Network for Undergraduate Societies (BONUS), London, UK
| | - Vatsala Khurana
- William Harvey Research Institute, Queen Mary University of London, London, UK
| | - Aruni Ghose
- Department of Medical Oncology, Barts Cancer Centre, St Bartholomew's Hospital, Barts Health NHS Trust, London, UK
- Department of Medical Oncology, Medway NHS Foundation Trust, Gillingham, Kent, UK
- Department of Medical Oncology, Mount Vernon Cancer Centre, Mount Vernon and Watford NHS Trust, Watford, UK
| | - Adheesh Ghosh
- UCL Cancer Institute, University College London, London, UK
| | - Ishika Mahajan
- Department of Oncology, Lincoln Oncology Centre, Lincoln County Hospital, United Lincolnshire Hospitals NHS Trust, Lincoln, UK
| | - Stergios Boussios
- Department of Medical Oncology, Medway NHS Foundation Trust, Gillingham, Kent, UK.
- Faculty of Life Sciences & Medicine, School of Cancer & Pharmaceutical Sciences, King's College London, London, UK.
- Kent and Medway Medical School, University of Kent, Canterbury, Kent, UK.
- Faculty of Medicine, Health, and Social Care, Canterbury Christ Church University, Canterbury, UK.
- AELIA Organization, 9th Km Thessaloniki-hermi, 57001, Thessaloniki, Greece.
| | - Akash Maniam
- Department of Medical Oncology, Portsmouth Hospitals University NHS Trust, Portsmouth, UK
- Faculty of Science and Health, School of Pharmacy and Biomedical Sciences, University of Portsmouth, Portsmouth, UK
- Caribbean Cancer Research Institute, Port of Spain, Trinidad and Tobago
| | - Olubukola Ayodele
- Department of Medical Oncology, University Hospitals of Leicester NHS Trust, Leicester, UK
- Leicester Cancer Research Centre, University of Leicester, Leicester, UK
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Oosthuizen J, Van der Merwe NC, Kotze MJ. Navigating the genetic landscape of breast cancer in South Africa amidst a developing healthcare system. Front Genet 2024; 14:1330946. [PMID: 38259622 PMCID: PMC10800608 DOI: 10.3389/fgene.2023.1330946] [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: 10/31/2023] [Accepted: 12/19/2023] [Indexed: 01/24/2024] Open
Abstract
Breast cancer is a significant global health issue as it represents the leading cause of death in women worldwide. In 2021, the World Health Organization established the Global Breast Cancer Initiative framework with the aim to reduce the breast cancer mortality rate by the year 2040. In countries with developing healthcare systems, such as South Africa, the implementation of first-world technologies has been slow. We provide an overview of the strides taken to improve the cost-effectiveness of genetic service delivery for breast cancer patients in South Africa - from advances in the technology utilized for BRCA founder genotyping to variant screening in moderate-to high-penetrance genes. We furthermore reflect on research undertaken to improve accessibility by means of population-directed point-of-care genetic testing that is ideal for use in a primary healthcare setting. We also report on a pilot study utilizing exome sequencing at the intersection between research and service delivery. Finally, we discuss and conclude on the controversies, research gaps, and future prospects based on the most recent developments in first-world countries that are implementable in developing countries to improve early detection of breast cancer and overall disease management.
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Affiliation(s)
- Jaco Oosthuizen
- Division of Human Genetics, National Health Laboratory Service, Bloemfontein, South Africa
- Division of Human Genetics, Faculty of Health Sciences, University of the Free State, Bloemfontein, South Africa
| | - Nerina C. Van der Merwe
- Division of Human Genetics, National Health Laboratory Service, Bloemfontein, South Africa
- Division of Human Genetics, Faculty of Health Sciences, University of the Free State, Bloemfontein, South Africa
| | - Maritha J. Kotze
- Division of Chemical Pathology, Department of Pathology, National Health Laboratory Service, Tygerberg Hospital, Cape Town, South Africa
- Division of Chemical Pathology, Department of Pathology, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa
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Christowitz C, Olivier DW, Schneider JW, Kotze MJ, Engelbrecht AM. Incorporating functional genomics into the pathology-supported genetic testing framework implemented in South Africa: A future view of precision medicine for breast carcinomas. MUTATION RESEARCH. REVIEWS IN MUTATION RESEARCH 2024; 793:108492. [PMID: 38631437 DOI: 10.1016/j.mrrev.2024.108492] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2023] [Revised: 02/25/2024] [Accepted: 04/11/2024] [Indexed: 04/19/2024]
Abstract
A pathology-supported genetic testing (PSGT) framework was established in South Africa to improve access to precision medicine for patients with breast carcinomas. Nevertheless, the frequent identification of variants of uncertain significance (VUSs) with the use of genome-scale next-generation sequencing has created a bottleneck in the return of results to patients. This review highlights the importance of incorporating functional genomics into the PSGT framework as a proposed initiative. Here, we explore various model systems and experimental methods available for conducting functional studies in South Africa to enhance both variant classification and clinical interpretation. We emphasize the distinct advantages of using in vitro, in vivo, and translational ex vivo models to improve the effectiveness of precision oncology. Moreover, we highlight the relevance of methodologies such as protein modelling and structural bioinformatics, multi-omics, metabolic activity assays, flow cytometry, cell migration and invasion assays, tube-formation assays, multiplex assays of variant effect, and database mining and machine learning models. The selection of the appropriate experimental approach largely depends on the molecular mechanism of the gene under investigation and the predicted functional effect of the VUS. However, before making final decisions regarding the pathogenicity of VUSs, it is essential to assess the functional evidence and clinical outcomes under current variant interpretation guidelines. The inclusion of a functional genomics infrastructure within the PSGT framework will significantly advance the reclassification of VUSs and enhance the precision medicine pipeline for patients with breast carcinomas in South Africa.
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Affiliation(s)
- Claudia Christowitz
- Department of Physiological Sciences, Faculty of Science, Stellenbosch University, Stellenbosch 7600, South Africa.
| | - Daniel W Olivier
- Department of Physiological Sciences, Faculty of Science, Stellenbosch University, Stellenbosch 7600, South Africa; Division of Chemical Pathology, Department of Pathology, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town 7505, South Africa
| | - Johann W Schneider
- Division of Anatomical Pathology, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town 7505, South Africa; National Health Laboratory Service, Tygerberg Hospital, Cape Town 7505, South Africa
| | - Maritha J Kotze
- Division of Chemical Pathology, Department of Pathology, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town 7505, South Africa; National Health Laboratory Service, Tygerberg Hospital, Cape Town 7505, South Africa
| | - Anna-Mart Engelbrecht
- Department of Physiological Sciences, Faculty of Science, Stellenbosch University, Stellenbosch 7600, South Africa; Department of Global Health, African Cancer Institute, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town 7505, South Africa
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Shain J, Michel A, May MS, Qunaj L, El-Sadr W, Chung WK, Appelbaum PS, Jacobson JS, Justman J, Neugut AI. Cancer genetic mutation prevalence in sub-Saharan Africa: A review of existing data. Semin Oncol 2023; 50:123-130. [PMID: 38171987 DOI: 10.1053/j.seminoncol.2023.12.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/20/2023] [Revised: 12/15/2023] [Accepted: 12/16/2023] [Indexed: 01/05/2024]
Abstract
BACKGROUND Cancer represents a leading cause of death worldwide. Germline mutations in several genes increase the risk of developing several cancers, including cancers of the breast, ovary, pancreas, colorectum, and melanoma. An understanding of the population prevalence of pathogenic germline variants can be helpful in the design of public health interventions, such as genetic testing, which has downstream implications for cancer screening, prevention, and treatment. While population-based studies of pathogenic germline variants exist, most such studies have been conducted in White populations. Limited data exist regarding the prevalence of germline mutations within sub-Saharan African populations. MATERIALS AND METHODS We identified countries defined as sub-Saharan Africa by the World Bank and conducted a scoping literature review using PubMed. For each country, we identified and summarized studies that focused on the prevalence of germline genetic mutations with sample sizes >10 and in a population directly from sub-Saharan Africa, either with or without diseases associated with the relevant genetic mutations. Studies that evaluated the prevalence of somatic or likely benign variants were excluded. RESULTS Within the 48 countries in sub-Saharan Africa, we identified 34 studies which meet the inclusion criteria. Twenty studies were conducted in South Africa, Nigeria, or Burkina Faso; four countries had more than two published papers. We found that 33 of 48 countries in sub-Saharan Africa lacked any genetic studies. Notably, there has been an increase in relevant studies starting in 2020. Importantly, of the 34 studies identified, 29 included data on BRCA1 or BRCA2. Data on the prevalence of mutations contributing to familial cancer syndromes other than BRCA1 and BRCA2 was limited. CONCLUSIONS While some progress has been made towards understanding the prevalence of germline mutations in cancer susceptibility genes, the characterization of genetic mutations among sub-Saharan African populations remains strikingly incomplete. Given the genetic diversity in the region, there remains a great need for large-scale, population-based studies to understand the prevalence of germline pathogenic variants and adequately capture all the subpopulations in this part of the world.
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Affiliation(s)
- Joshua Shain
- Department of Medicine, Vagelos College of Physicians & Surgeons, Columbia University, New York, NY
| | - Alissa Michel
- Department of Medicine, Vagelos College of Physicians & Surgeons, Columbia University, New York, NY
| | - Michael S May
- Department of Medicine, Vagelos College of Physicians & Surgeons, Columbia University, New York, NY
| | - Lindor Qunaj
- Department of Medicine, Vagelos College of Physicians & Surgeons, Columbia University, New York, NY
| | - Wafaa El-Sadr
- Department of Medicine, Vagelos College of Physicians & Surgeons, Columbia University, New York, NY; Herbert Irving Comprehensive Cancer Center, Vagelos College of Physicians & Surgeons, Columbia University, New York, NY; Department of Epidemiology and ICAP, Mailman School of Public Health, Columbia University, New York, NY
| | - Wendy K Chung
- Department of Medicine, Vagelos College of Physicians & Surgeons, Columbia University, New York, NY; Department of Psychiatry, Vagelos College of Physicians & Surgeons, Columbia University, New York, NY; Department of Epidemiology and ICAP, Mailman School of Public Health, Columbia University, New York, NY
| | - Paul S Appelbaum
- Herbert Irving Comprehensive Cancer Center, Vagelos College of Physicians & Surgeons, Columbia University, New York, NY; Department of Epidemiology and ICAP, Mailman School of Public Health, Columbia University, New York, NY
| | - Judith S Jacobson
- Department of Epidemiology and ICAP, Mailman School of Public Health, Columbia University, New York, NY
| | - Jessica Justman
- Department of Medicine, Vagelos College of Physicians & Surgeons, Columbia University, New York, NY; Department of Epidemiology and ICAP, Mailman School of Public Health, Columbia University, New York, NY
| | - Alfred I Neugut
- Department of Medicine, Vagelos College of Physicians & Surgeons, Columbia University, New York, NY; Department of Epidemiology and ICAP, Mailman School of Public Health, Columbia University, New York, NY.
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Isiklar AD, Aliyeva L, Yesilyurt A, Soyder A, Basaran G. Frequency of germline pathogenic variants in breast cancer predisposition genes among young Turkish breast cancer patients. Breast Cancer Res Treat 2023; 202:297-304. [PMID: 37615792 DOI: 10.1007/s10549-023-07074-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2023] [Accepted: 08/06/2023] [Indexed: 08/25/2023]
Abstract
PURPOSE One of the most important risk factors for hereditary breast and ovarian cancer is young age. We aim to report the frequency of pathogenic/likely pathogenic variants in breast cancer predisposing genes in young (≤ 40 years old) breast cancer patients who undergone 26-gene inherited cancer panel at our Breast Health Center. METHODS Medical records of breast cancer patients who were referred to genetic counseling based on NCCN criteria and were ≤ 40 years of age are reviewed. The frequency of germline pathogenic/likely pathogenic variants who undergone 26-gene inherited cancer panel was analyzed. RESULTS Among 414 breast cancer patients who were ≤ 40 years of age, 308 undergone 26-gene inherited cancer panel and 108 had next generation sequencing (NGS)-based BRCA 1 and 2 genetic testing. Median age was 35 (22-40), Family history in first degree relatives was present in 14% of patients. Forty-five percent of patients met one of the NCCN criteria for genetic testing, 41% of them met two criteria, and 14% of patients fulfilled ≥ 3 criteria. Seventy pathogenic/likely pathogenic variants (PV/LPV) were found in 65 (21%) patients. PV/LPs in BRCA genes and non-BRCA genes represented 53% and 44% of all PV/LPVs, accounting for 12% and 10% of patients in the study cohort respectively. Two PVs were present in 5 patients and eleven PVs were novel. The most common PVs were in BRCA 1 (n:18), BRCA 2 (n:19), ATM (n:7), CHEK2 (n:7) and TP53 (n:5) genes. Thirty-one percent of the patients with triple-negative tumors and 25% of the patients with hormone receptor-positive tumors had PV/LPVs with panel testing. Family history in first degree relatives (p = 0.029), the number of met NCCN criteria (p = 0.036) and axillary nodal involvement (p = 0.000) were more common in patients with PVs. When combined with patient group (n:106) who had only BRCA1 and 2 gene testing, 16% of Turkish breast cancer patients ≤ 40 years of age had PVs in BRCA genes. CONCLUSION One fifth of Turkish breast cancer patients ≤ 40 years of age had at least one PV/LPV in breast cancer predisposing genes with 26-gene inherited cancer panel. The frequency of PV/LPVs was higher in triple-negative young-onset patients compared to hormone receptor and Her-2 positive subtypes. Our findings regarding to frequency PV/LPVs in BRCA 1/2 and non-BRCA genes in young-onset breast cancer patients are in line with the literature.
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Affiliation(s)
- Aysun Dauti Isiklar
- Department of Internal Medicine, Acibadem Altunizade Hospital, Altunizade District, Yurtcan St. No: 1, Uskudar, Istanbul, Turkey.
| | - Lamiya Aliyeva
- Department of Medical Genetics, Acibadem Mehmet Ali Aydinlar University, School of Medicine, Halkali Merkez, Turgut Ozal Bulvari No: 16, 34303, Kucukcekmece, Istanbul, Turkey
| | - Ahmet Yesilyurt
- Acibadem Labgen Genetic Diagnosis Center, İçerenköy Kerem Aydınlar Campus, Kayışdağı Cd. No: 32, Atasehir, Istanbul, Turkey
| | - Aykut Soyder
- Department of General Surgery, Acibadem Mehmet Ali Aydinlar University, School of Medicine, Altunizade District, Yurtcan St. No: 1, Uskudar, Istanbul, Turkey
| | - Gul Basaran
- Department of Internal Medicine and Medical Oncology, Acibadem Mehmet Ali Aydinlar University, School of Medicine, Altunizade District, Yurtcan St. No: 1, Uskudar, Istanbul, Turkey
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Vadakedath S, Kandi V, Ca J, Vijayan S, Achyut KC, Uppuluri S, Reddy PKK, Ramesh M, Kumar PP. Mitochondrial Deoxyribonucleic Acid (mtDNA), Maternal Inheritance, and Their Role in the Development of Cancers: A Scoping Review. Cureus 2023; 15:e39812. [PMID: 37397663 PMCID: PMC10314188 DOI: 10.7759/cureus.39812] [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] [Accepted: 05/31/2023] [Indexed: 07/04/2023] Open
Abstract
Mitochondrial DNA (mtDNA) is a small, circular, double-stranded DNA inherited from the mother during fertilization. Evolutionary evidence supported by the endosymbiotic theory identifies mitochondria as an organelle that could have descended from prokaryotes. This may be the reason for the independent function and inheritance pattern shown by mtDNA. The unstable nature of mtDNA due to the lack of protective histones, and effective repair systems make it more vulnerable to mutations. The mtDNA and its mutations could be maternally inherited thereby predisposing the offspring to various cancers like breast and ovarian cancers among others. Although mitochondria are considered heteroplasmic wherein variations among the multiple mtDNA genomes are noticed, mothers can have mitochondrial populations that are homoplasmic for a given mitochondrial mutation. Homoplasmic mitochondrial mutations may be transmitted to all maternal offspring. However, due to the complex interplay between the mitochondrial and nuclear genomes, it is often difficult to predict disease outcomes, even with homoplasmic mitochondrial populations. Heteroplasmic mtDNA mutations can be maternally inherited, but the proportion of mutated alleles differs markedly between offspring within one generation. This led to the genetic bottleneck hypothesis, explaining the rapid changes in allele frequency witnessed during the transmission of mtDNA from one generation to the next. Although a physical reduction in mtDNA has been demonstrated in several species, a comprehensive understanding of the molecular mechanisms is yet to be demonstrated. Despite initially thought to be limited to the germline, there is evidence that blockages exist in different cell types during development, perhaps explaining why different tissues in the same organism contain different levels of mutated mtDNA. In this review, we comprehensively discuss the potential mechanisms through which mtDNA undergoes mutations and the maternal mode of transmission that contributes to the development of tumors, especially breast and ovarian cancers.
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Affiliation(s)
| | - Venkataramana Kandi
- Clinical Microbiology, Prathima Institute of Medical Sciences, Karimnagar, IND
| | - Jayashankar Ca
- Internal Medicine, Vydehi Institute of Medical Sciences and Research Centre, Bengaluru, IND
| | - Swapna Vijayan
- Pediatrics, Sir CV Raman General Hospital, Bengaluru, IND
| | - Kushal C Achyut
- Internal Medicine, Vydehi Institute of Medical Sciences and Research Centre, Bangalore, IND
| | - Shivani Uppuluri
- Internal Medicine, Vydehi Institute of Medical Sciences and Research Centre, Bengaluru, IND
| | - Praveen Kumar K Reddy
- General Medicine, Vydehi Institute of Medical Sciences and Research Centre, Bengaluru, IND
| | - Monish Ramesh
- Internal Medicine, Vydehi Institute of Medical Sciences and Research Centre, Bengaluru, IND
| | - P Pavan Kumar
- General Medicine, Vydehi Institute of Medical Sciences and Research Centre, Bengaluru, IND
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