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Grigore LG, Radoi VE, Serban A, Mihai AD, Stoica I. The Molecular Detection of Germline Mutations in the BRCA1 and BRCA2 Genes Associated with Breast and Ovarian Cancer in a Romanian Cohort of 616 Patients. Curr Issues Mol Biol 2024; 46:4630-4645. [PMID: 38785549 PMCID: PMC11119367 DOI: 10.3390/cimb46050281] [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: 04/15/2024] [Revised: 05/07/2024] [Accepted: 05/10/2024] [Indexed: 05/25/2024] Open
Abstract
The objective of this study was to identify and classify the spectrum of mutations found in the BRCA1 and BRCA2 genes associated with breast and ovarian cancer in female patients in Romania. Germline BRCA1 and BRCA2 mutations were investigated in a cohort of 616 female patients using NGS and/or MLPA methods followed by software-based data analysis and classification according to international guidelines. Out of the 616 female patients included in this study, we found that 482 patients (78.2%) did not have any mutation present in the two genes investigated; 69 patients (11.2%) had a BRCA1 mutation, 34 (5.5%) had a BRCA2 mutation, and 31 (5%) presented different type of mutations with uncertain clinical significance, moderate risk or a large mutation in the BRCA1 gene. Our investigation indicates the most common mutations in the BRCA1 and BRCA2 genes, associated with breast and ovarian cancer in the Romanian population. Our results also bring more data in support of the frequency of the c.5266 mutation in the BRCA1 gene, acknowledged in the literature as a founder mutation in Eastern Europe. We consider that the results of our study will provide necessary data regarding BRCA1 and BRCA2 mutations that would help to create a genetic database for the Romanian population.
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Affiliation(s)
- Liliana-Georgiana Grigore
- Doctoral School of Biology, Faculty of Biology, University of Bucharest, 030018 Bucharest, Romania
- Personal Genetics, 010987 Bucharest, Romania
| | - Viorica-Elena Radoi
- Department of Medical Genetics, “Carol Davila” University of Medicine and Pharmacy, 020021 Bucharest, Romania
- “Alessandrescu-Rusescu” National Institute for Maternal and Child Health, 20382 Bucharest, Romania
| | | | | | - Ileana Stoica
- Department of Genetics, Faculty of Biology, University of Bucharest, 030018 Bucharest, Romania
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Kechin A, Boyarskikh U, Barinov A, Tanas A, Kazakova S, Zhevlova A, Khrapov E, Subbotin S, Mishukova O, Kekeeva T, Demidova I, Filipenko M. A spectrum of BRCA1 and BRCA2 germline deleterious variants in ovarian cancer in Russia. Breast Cancer Res Treat 2023; 197:387-395. [PMID: 36367610 DOI: 10.1007/s10549-022-06782-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Accepted: 10/23/2022] [Indexed: 11/13/2022]
Abstract
PURPOSE Pathogenic variants (PVs) in BRCA1 and BRCA2 genes are essential biomarkers of an increased breast and ovarian cancer risk and tumor sensitivity to poly ADP ribose polymerase inhibitors. In Russia, eight PVs were thought to be the most common, among which BRCA1 c.5266dup is the most frequently identified one. METHODS We show the distribution of BRCA1/2 PVs identified with quantitative PCR and targeted next-generation sequencing in 1399 ovarian cancer patients recruited into the study from 72 Russian regions in 2015-2021. RESULTS The most abundant PVs were c.5266dup (41.0%), c.4035del (7.0%), c.1961del (6.3%), c.181 T > G (5.2%), c.3756_3759del (1.8%), c.3700_3704del (1.5%), and c.68_69del (1.5%), all found in BRCA1 and known to be recurrent in Russia. Several other frequent PVs were identified: c.5152 + 1G > T (1.2%), c.1687C > T (1.0%), c.4689C > G (0.9%), c.1510del (0.6%), c.2285_2286del (0.6%) in the BRCA1 gene; and c.5286 T > G (1.2%), c.2808_2811del (0.8%), c.3847_3848del (0.8%), c.658_659del (0.7%), c.7879A > T (0.6%), in the BRCA2 gene. For the most common PV in the BRCA2 gene c.5286 T > G, we suggested that it arose about 700 years ago and is a new founder mutation. CONCLUSION This study extends our knowledge about the BRCA1 and BRCA2 pathogenic variants variability.
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Affiliation(s)
- Andrey Kechin
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, 630090, Russia. .,Novosibirsk State University, Novosibirsk, 630090, Russia.
| | - Ulyana Boyarskikh
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, 630090, Russia
| | - Alexey Barinov
- Moscow City Oncology Hospital No 62 of the Moscow Health Department, Istra, 143423, Russia
| | - Alexander Tanas
- Research Centre for Medical Genetics, Moscow, 115522, Russia
| | | | | | - Evgeniy Khrapov
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, 630090, Russia
| | - Sergey Subbotin
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, 630090, Russia
| | - Olga Mishukova
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, 630090, Russia
| | - Tatiana Kekeeva
- Research Centre for Medical Genetics, Moscow, 115522, Russia
| | - Irina Demidova
- Moscow City Oncology Hospital No 62 of the Moscow Health Department, Istra, 143423, Russia
| | - Maxim Filipenko
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, 630090, Russia.,Novosibirsk State University, Novosibirsk, 630090, Russia
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Sokolenko AP, Sultanova LV, Stepanov IA, Romanko AA, Venina AR, Sokolova TN, Musayeva HS, Tovgereeva MY, Magomedova MK, Akhmatkhanov KU, Vagapova EI, Suleymanov E, Vasilyeva EV, Bakaeva EK, Bizin IV, Aleksakhina SN, Imyanitov EN. Strong founder effect for BRCA1 c.3629_3630delAG pathogenic variant in Chechen patients with breast or ovarian cancer. Cancer Med 2022; 12:3167-3171. [PMID: 36000185 PMCID: PMC9939208 DOI: 10.1002/cam4.5159] [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: 04/30/2022] [Revised: 07/21/2022] [Accepted: 08/03/2022] [Indexed: 11/08/2022] Open
Abstract
Coding sequences of BRCA1, BRCA2, ATM, TP53, and PALB2 genes were analyzed in 68 consecutive Chechen patients with high-grade serous ovarian cancer (HGSOC). Pathogenic BRCA1/2 variants were identified in 15 (22%) out of 68 HGSOC cases. Nine out of ten patients with BRCA1 pathogenic alleles carried the same deletion (c.3629_3630delAG), and three out of five BRCA2 heterozygotes had Q3299X allele. The analysis of 49 consecutive patients with triple-negative breast cancer (TNBC) revealed 3 (6%) additional BRCA1 heterozygotes. All women with BRCA1 c.3629_3630delAG allele also carried linked c.1067G>A (Q356R) single nucleotide polymorphism, indicating that this is a genuine founder variant but not a mutational hotspot. An ATM truncating allele was detected in one HGSOC patient. There were no women with TP53 or PALB2 germline alterations. Genetic analysis of non-selected HGSOC patients is an efficient tool for the identification of ethnicity-specific BRCA1/2 pathogenic variants.
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Affiliation(s)
- Anna P. Sokolenko
- Department of Tumor Growth BiologyN.N. Petrov Institute of OncologySaint‐PetersburgRussia,Department of Medical GeneticsSt.‐Petersburg Pediatric Medical UniversitySaint‐PetersburgRussia
| | | | - Ilya A. Stepanov
- Department of Tumor Growth BiologyN.N. Petrov Institute of OncologySaint‐PetersburgRussia
| | - Alexandr A. Romanko
- Department of Tumor Growth BiologyN.N. Petrov Institute of OncologySaint‐PetersburgRussia,Department of Medical GeneticsSt.‐Petersburg Pediatric Medical UniversitySaint‐PetersburgRussia
| | - Aigul R. Venina
- Department of Tumor Growth BiologyN.N. Petrov Institute of OncologySaint‐PetersburgRussia
| | - Tatiana N. Sokolova
- Department of Tumor Growth BiologyN.N. Petrov Institute of OncologySaint‐PetersburgRussia
| | | | | | | | | | | | | | - Elena V. Vasilyeva
- Department of Tumor Growth BiologyN.N. Petrov Institute of OncologySaint‐PetersburgRussia
| | - Elvina Kh. Bakaeva
- Department of Tumor Growth BiologyN.N. Petrov Institute of OncologySaint‐PetersburgRussia
| | - Ilya V. Bizin
- Department of Tumor Growth BiologyN.N. Petrov Institute of OncologySaint‐PetersburgRussia
| | | | - Evgeny N. Imyanitov
- Department of Tumor Growth BiologyN.N. Petrov Institute of OncologySaint‐PetersburgRussia,Department of Medical GeneticsSt.‐Petersburg Pediatric Medical UniversitySaint‐PetersburgRussia,Department of OncologyI.I. Mechnikov North‐Western Medical UniversitySaint‐PetersburgRussia
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Jankowski M, Daca-Roszak P, Obracht-Prondzyński C, Płoski R, Lipska-Ziętkiewicz BS, Ziętkiewicz E. Genetic diversity in Kashubs: the regional increase in the frequency of several disease-causing variants. J Appl Genet 2022; 63:691-701. [PMID: 35971028 PMCID: PMC9637066 DOI: 10.1007/s13353-022-00713-z] [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: 03/22/2022] [Revised: 07/12/2022] [Accepted: 07/18/2022] [Indexed: 12/02/2022]
Abstract
Differential distribution of genetic variants’ frequency among human populations is caused by the genetic drift in isolated populations, historical migrations, and demography. Some of these variants are identical by descent and represent founder mutations, which — if pathogenic in nature — lead to the increased frequency of otherwise rare diseases. The detection of the increased regional prevalence of pathogenic variants may shed light on the historical processes that affected studied populations and can help to develop effective screening and diagnostic strategies as a part of personalized medicine. Here, we discuss the specific genetic diversity in Kashubs, the minority group living in northern Poland, reflected in the biased distribution of some of the repetitively found disease-causing variants. These include the following: (1) c.662A > G (p.Asp221Gly) in LDLR, causing heterozygous familial hypercholesterolemia; (2) c.3700_3704del in BRCA1, associated with hereditary breast and ovarian cancer syndrome; (3) c.1528G > C (p.Glu510Gln) in HADHA, seen in long-chain 3-hydroxy acyl-CoA dehydrogenase (LCHAD) deficiency, and (4) c.1032delT in NPHS2, associated with steroid-resistant nephrotic syndrome.
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Affiliation(s)
- Maciej Jankowski
- Department of Biology and Medical Genetics, Medical University of Gdansk, Gdansk, Poland
| | | | | | - Rafał Płoski
- Department of Medical Genetics, Medical University of Warsaw, Warsaw, Poland
| | - Beata S Lipska-Ziętkiewicz
- Clinical Genetics Unit, Department of Biology and Medical Genetics, Medical University of Gdansk, Gdansk, Poland. .,Centre for Rare Diseases, Medical University of Gdansk, Gdansk, Poland.
| | - Ewa Ziętkiewicz
- Institute of Human Genetics, Polish Academy of Sciences, Poznan, Poland.
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Rajagopal T, Seshachalam A, Jothi A, Rathnam KK, Talluri S, Venkatabalasubranian S, Dunna NR. Analysis of pathogenic variants in BRCA1 and BRCA2 genes using next-generation sequencing in women with triple negative breast cancer from South India. Mol Biol Rep 2022; 49:3025-3032. [PMID: 35020120 DOI: 10.1007/s11033-022-07129-2] [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: 08/14/2021] [Accepted: 01/05/2022] [Indexed: 11/30/2022]
Abstract
BACKGROUND The frequency of triple-negative breast cancer (TNBC) incidence varies among different populations suggesting the involvement of genetic components towards TNBC development. Previous studies have reported that BRCA1/2 germline mutations confer a lifetime risk of developing TNBC. However, there is hardly any information regarding the common pathogenic variants (PVs) in BRCA1/2 genes that contribute to TNBC in the Indian population. Hence, we screened for PVs in BRCA1/2 and their association with clinico-pathological features in TNBC patients. METHODS AND RESULTS The study recruited 59 TNBC patients without hereditary breast and ovarian cancer (HBOC) from South India. The entire BRCA1 and BRCA2 genes were sequenced for the 59 patients using the Illumina HiSeq X Ten sequencer. Among the 59 TNBC genomic DNA samples sequenced, BRCA mutations were identified in 8 patients (13.6%), BRCA1 mutations in 6 patients, and BRCA2 mutations in 2 patients. Among the 6 BRCA1 mutations, three were c.68_69delAG (185delAG) mutation. Remarkably, all the TNBC patients with BRCA mutations exhibited higher-grade tumors (grade 2 or 3). However, among all the BRCA mutation carriers, only one patient with a BRCA2 mutation (p.Glu1879Lys) developed metastasis. CONCLUSION Our data advocates that South Indian women with higher grade TNBC tumors and without HBOC could be considered for BRCA mutation screening, thereby enabling enhanced decision-making and preventive therapy.
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Affiliation(s)
- Taruna Rajagopal
- Cancer Genomics Laboratory, Department of Biotechnology, School of Chemical and Biotechnology, SASTRA - Deemed University, Thanjavur, 613 401, India
| | - Arun Seshachalam
- Department of Medical and Paediatric Oncology, Dr.G.V.N Cancer Institute, Singarathope, Trichy, 620 008, India
| | - Arunachalam Jothi
- Department of Bioinformatics, School of Chemical and Biotechnology, SASTRA - Deemed University, Thanjavur, 613 401, India
| | - Krishna Kumar Rathnam
- Department of Hemato Oncology - Medical Oncology and Bone Marrow Transplantation, Meenakshi Mission Hospital & Research Centre, Madurai, 625 107, India
| | - Srikanth Talluri
- Dana Farber Cancer Institute, Boston, MA, 02215, USA
- Veterans Administration Boston Healthcare System, West Roxbury, MA, 02132, USA
| | - Sivaramakrishnan Venkatabalasubranian
- Department of Genetic Engineering, Faculty of Engineering and Technology, SRM Institute of Science and Technology, Kattankulathur Campus, Chennai, Tamil Nadu, 603 203, India
| | - Nageswara Rao Dunna
- Cancer Genomics Laboratory, Department of Biotechnology, School of Chemical and Biotechnology, SASTRA - Deemed University, Thanjavur, 613 401, India.
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Hamdi Y, Mighri N, Boujemaa M, Mejri N, Ben Nasr S, Ben Rekaya M, Messaoud O, Bouaziz H, Berrazega Y, Rachdi H, Jaidane O, Daoud N, Zribi A, Ayari J, El Benna H, Labidi S, Ben Hassouna J, Haddaoui A, Rahal K, Benna F, Mrad R, Ben Ahmed S, Boussen H, Boubaker S, Abdelhak S. Identification of Eleven Novel BRCA Mutations in Tunisia: Impact on the Clinical Management of BRCA Related Cancers. Front Oncol 2021; 11:674965. [PMID: 34490083 PMCID: PMC8417726 DOI: 10.3389/fonc.2021.674965] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Accepted: 07/27/2021] [Indexed: 12/20/2022] Open
Abstract
Background Breast cancer is the world's most common cancer among women. It is becoming an increasingly urgent problem in low- and middle-income countries (LMICs) where a large fraction of women is diagnosed with advanced-stage disease and have no access to treatment or basic palliative care. About 5-10% of all breast cancers can be attributed to hereditary genetic components and up to 25% of familial cases are due to mutations in BRCA1/2 genes. Since their discovery in 1994 and 1995, as few as 18 mutations have been identified in BRCA genes in the Tunisian population. The aim of this study is to identify additional BRCA mutations, to estimate their contribution to the hereditary breast and ovarian cancers in Tunisia and to investigate the clinicopathological signatures associated with BRCA mutations. Methods A total of 354 patients diagnosed with breast and ovarian cancers, including 5 male breast cancer cases, have been investigated for BRCA1/2 mutations using traditional and/or next generation sequencing technologies. Clinicopathological signatures associated with BRCA mutations have also been investigated. Results In the current study, 16 distinct mutations were detected: 10 in BRCA1 and 6 in BRCA2, of which 11 are described for the first time in Tunisia including 3 variations that have not been reported previously in public databases namely BRCA1_c.915T>A; BRCA2_c.-227-?_7805+? and BRCA2_c.249delG. Early age at onset, family history of ovarian cancer and high tumor grade were significantly associated with BRCA status. BRCA1 carriers were more likely to be triple negative breast cancer compared to BRCA2 carriers. A relatively high frequency of contralateral breast cancer and ovarian cancer occurrence was observed among BRCA carriers and was more frequent in patients carrying BRCA1 mutations. Conclusion Our study provides new insights into breast and ovarian cancer genetic landscape in the under-represented North African populations. The prevalence assessment of novel and recurrent BRCA1/2 pathogenic mutations will enhance the use of personalized treatment and precise screening strategies by both affected and unaffected North African cancer cases.
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Affiliation(s)
- Yosr Hamdi
- Laboratory of Biomedical Genomics and Oncogenetics, LR20IPT05, Institut Pasteur de Tunis, University of Tunis El Manar, Tunis, Tunisia.,Laboratory of Human and Experimental Pathology, Institut Pasteur de Tunis, Tunis, Tunisia
| | - Najah Mighri
- Laboratory of Biomedical Genomics and Oncogenetics, LR20IPT05, Institut Pasteur de Tunis, University of Tunis El Manar, Tunis, Tunisia
| | - Maroua Boujemaa
- Laboratory of Biomedical Genomics and Oncogenetics, LR20IPT05, Institut Pasteur de Tunis, University of Tunis El Manar, Tunis, Tunisia
| | - Nesrine Mejri
- Laboratory of Biomedical Genomics and Oncogenetics, LR20IPT05, Institut Pasteur de Tunis, University of Tunis El Manar, Tunis, Tunisia.,Medical Oncology Department, Abderrahman Mami Hospital, Faculty of Medicine Tunis, University Tunis El Manar, Tunis, Tunisia
| | - Sonia Ben Nasr
- Laboratory of Biomedical Genomics and Oncogenetics, LR20IPT05, Institut Pasteur de Tunis, University of Tunis El Manar, Tunis, Tunisia.,Department of Medical Oncology, Military Hospital of Tunis, Tunis, Tunisia
| | - Mariem Ben Rekaya
- Laboratory of Biomedical Genomics and Oncogenetics, LR20IPT05, Institut Pasteur de Tunis, University of Tunis El Manar, Tunis, Tunisia.,UR17ES15, Oncotheranostic Biomarkers, Faculty of Medicine of Tunis, University Tunis El Manar, Tunis, Tunisia
| | - Olfa Messaoud
- Laboratory of Biomedical Genomics and Oncogenetics, LR20IPT05, Institut Pasteur de Tunis, University of Tunis El Manar, Tunis, Tunisia
| | - Hanen Bouaziz
- Laboratory of Biomedical Genomics and Oncogenetics, LR20IPT05, Institut Pasteur de Tunis, University of Tunis El Manar, Tunis, Tunisia.,Surgical Oncology Department, Salah Azaiez Institute of Cancer, Tunis, Tunisia
| | - Yosra Berrazega
- Medical Oncology Department, Abderrahman Mami Hospital, Faculty of Medicine Tunis, University Tunis El Manar, Tunis, Tunisia
| | - Haifa Rachdi
- Medical Oncology Department, Abderrahman Mami Hospital, Faculty of Medicine Tunis, University Tunis El Manar, Tunis, Tunisia
| | - Olfa Jaidane
- Surgical Oncology Department, Salah Azaiez Institute of Cancer, Tunis, Tunisia
| | - Nouha Daoud
- Medical Oncology Department, Abderrahman Mami Hospital, Faculty of Medicine Tunis, University Tunis El Manar, Tunis, Tunisia
| | - Aref Zribi
- Department of Medical Oncology, Military Hospital of Tunis, Tunis, Tunisia
| | - Jihene Ayari
- Department of Medical Oncology, Military Hospital of Tunis, Tunis, Tunisia
| | - Houda El Benna
- Laboratory of Biomedical Genomics and Oncogenetics, LR20IPT05, Institut Pasteur de Tunis, University of Tunis El Manar, Tunis, Tunisia.,Medical Oncology Department, Abderrahman Mami Hospital, Faculty of Medicine Tunis, University Tunis El Manar, Tunis, Tunisia
| | - Soumaya Labidi
- Laboratory of Biomedical Genomics and Oncogenetics, LR20IPT05, Institut Pasteur de Tunis, University of Tunis El Manar, Tunis, Tunisia.,Medical Oncology Department, Abderrahman Mami Hospital, Faculty of Medicine Tunis, University Tunis El Manar, Tunis, Tunisia
| | - Jamel Ben Hassouna
- Surgical Oncology Department, Salah Azaiez Institute of Cancer, Tunis, Tunisia
| | | | - Khaled Rahal
- Surgical Oncology Department, Salah Azaiez Institute of Cancer, Tunis, Tunisia
| | - Farouk Benna
- Department of Radiation Oncology, University of Tunis, Tunis, Tunisia
| | - Ridha Mrad
- Department of Human Genetics, Charles Nicolle Hospital, Tunis, Tunisia
| | - Slim Ben Ahmed
- Faculty of Medicine of Sousse Department of Medical Oncology Farhat Hached University Hospital University of Sousse, Sousse, Tunisia
| | - Hamouda Boussen
- Laboratory of Biomedical Genomics and Oncogenetics, LR20IPT05, Institut Pasteur de Tunis, University of Tunis El Manar, Tunis, Tunisia.,Medical Oncology Department, Abderrahman Mami Hospital, Faculty of Medicine Tunis, University Tunis El Manar, Tunis, Tunisia
| | - Samir Boubaker
- Laboratory of Biomedical Genomics and Oncogenetics, LR20IPT05, Institut Pasteur de Tunis, University of Tunis El Manar, Tunis, Tunisia.,Laboratory of Human and Experimental Pathology, Institut Pasteur de Tunis, Tunis, Tunisia
| | - Sonia Abdelhak
- Laboratory of Biomedical Genomics and Oncogenetics, LR20IPT05, Institut Pasteur de Tunis, University of Tunis El Manar, Tunis, Tunisia
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Frequency of mutations in BRCA genes and other candidate genes in high-risk probands or probands with breast or ovarian cancer in the Czech Republic. Mol Biol Rep 2020; 47:2763-2769. [PMID: 32180084 DOI: 10.1007/s11033-020-05378-7] [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: 11/21/2019] [Accepted: 03/12/2020] [Indexed: 01/08/2023]
Abstract
Breast cancer is currently the most common form of malignant tumour in womenboth in the Czech Republic and in most countries of the western world, and its incidence is constantly increasing. Many risk factors are known to play a major role in the development of this form of cancer. One of them is genetics, especially the BRCA1/2 genes. A higher risk of ovarian cancer is also associated with these genes. With the development of laboratory diagnostics massive parallel sequencing methods (NGS) are now routinely employed, enabling the detection of other pathogenic sequence variants, or variants of uncertain significance (VUS) not previously detected. Besides the high penetrance BRCA1/2 genes, medium and low penetrant genes also come to the fore. There were 2046 probands examined in the study, men and women, mainly from eastern part of the Czech Republic. These were selected for a genetic examination, after meeting indication criteria (probands from high-risk families or with breast or ovarian cancer). From this group only women, 2033 probands, were selected and were given a genetic examination for the possible presence of patogenic sequence variants in BRCA1/2 genes, or other candidate genes. Analyses were conducted in the laboratory using DHPLC or next generation sequencing. MLPA method is used for large rearrangements in genes. From all examined women 212 mutations were detected. The most mutations (128) were found in the BRCA1 gene (60%). In the BRCA2 gene 71 mutations (34%) were found and 13 more mutations (6%) were detected in another candidate genes (CHEK2, PALB2, ERCC4). The most frequent sequence variant was c.5266dupC in the BRCA1 gene. The results show that 72% of women with a confirmed mutation in the BRCA1 gene and 77.5% of women with the sequence variant BRCA2, already had breast cancer and 16.4% of women with BRCA1 and 7% of women with BRCA2 already had ovarian cancer. Only 21 high risk families used the possibility to be tested and had undergone targeted mutation testing. The study results suggest a reflection of the causes and needs for examination of patients and women predisposed to breast or ovarian cancer.
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