Absence of allelic variants in the BRCA1 gene of northern Brazilian breast cancer patients who met criteria for hereditary predisposition: a transversal study

Autores/as

DOI:

https://doi.org/10.21527/2176-7114.2026.51.16745

Palabras clave:

mutation, breast neoplasms, genes, BRCA, Brazil

Resumen

Background - It is estimated that about 5 to 10% of all breast cancer cases have a hereditary context, in which tumor progression occurs through the activation or repression of important genes in the germ cell line of an individual. BRCA1 is the most penetrant gene associated with breast cancer, and the presence of pathogenic mutations in its sequence increases the risk of developing this neoplasm to 45-75%. In the northern region of Brazil, the largest geographical region of the country, only two studies have been conducted to date to detect allelic variants in this gene. Objectives - This is a transversal study that aimed to assess pathogenic mutations in the BRCA1 gene of breast cancer patients treated in a public health reference unit for cancer research and treatment in the western Amazon. Design, setting and methods- Genetic testing was performed using polymerase chain reaction (PCR) methods and Sanger sequencing of seven important coding regions of the BRCA1 gene. Results - No variants were found in the sequences studied, which may indicate that the frequency of pathogenic mutations in the BRCA1 gene in this population is low. Conclusions - Although no pathogenic mutations were identified in the analyzed sequences, this study provides epidemiological data for a better understanding of the Brazilian mutational profile of genes associated with breast cancer.

Citas

1. Park KS, Lee W, Seong MW, Kong SY, Lee KA, Ha JS, et al. A Population-Based Analysis of BRCA1/2 Genes and Associated Breast and Ovarian Cancer Risk in Korean Patients: A Multicenter Cohort Study. Cancers (Basel) [Internet]. 2021 May 2;13(9):2192. Available from: https://www.mdpi.com/2072-6694/13/9/2192

2. Sung H, Ferlay J, Siegel RL, Laversanne M, Soerjomataram I, Jemal A, et al. Global Cancer Statistics 2020: GLOBOCAN Estimates of Incidence and Mortality Worldwide for 36 Cancers in 185 Countries. CA Cancer J Clin [Internet]. 2021 May 4;71(3):209–49. Available from: https://onlinelibrary.wiley.com/doi/10.3322/caac.21660

3. Abdulrashid K, Alhussaini N, Ahmed W, Thalib L. Prevalence of BRCA mutations among hereditary breast and/or ovarian cancer patients in Arab countries: Systematic review and meta-analysis. BMC Cancer [Internet]. 2019 [cited 2019 Sep 23];19(1). Available from: https://doi.org/10.1186/s12885-019-5463-1

4. Hodgson A, Turashvili G. Pathology of Hereditary Breast and Ovarian Cancer. Front Oncol [Internet]. 2020 Sep 29;10. Available from: https://www.frontiersin.org/article/10.3389/fonc.2020.531790/full

5. Miki Y, Swensen J, Shattuck-Eidens D, Futreal PA, Harshman K, Tavtigian S, et al. A Strong Candidate for the Breast and Ovarian Cancer Susceptibility Gene BRCA1. Science (1979) [Internet]. 1994 Oct 7 [cited 2021 Oct 28];266(5182):66–71. Available from: https://www.science.org/doi/10.1126/science.7545954

6. Hatano Y, Tamada M, Matsuo M, Hara A. Molecular Trajectory of BRCA1 and BRCA2 Mutations. Front Oncol [Internet]. 2020 Mar 25 [cited 2020 Mar 28];10:361. Available from: https://www.frontiersin.org/article/10.3389/fonc.2020.00361/full

7. Esteves VF, Thuler LCS, Amêndola LC, Koifman RJ, Koifman S, Frankel PP, et al. Prevalence of BRCA1 and BRCA2 gene mutations in families with medium and high risk of breast and ovarian cancer in Brazil. Brazilian Journal of Medical and Biological Research [Internet]. 2009 May [cited 2022 Apr 18];42(5):453–7. Available from: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2009000500009&lng=en&tlng=en

8. Guindalini RSC, Viana DV, Kitajima JPFW, Rocha VM, López RVM, Zheng Y, et al. Detection of germline variants in Brazilian breast cancer patients using multigene panel testing. Sci Rep [Internet]. 2022 Dec 9;12(1):4190. Available from: https://www.nature.com/articles/s41598-022-07383-1

9. Felix GES, Guindalini RSC, Zheng Y, Walsh T, Sveen E, Lopes TMM, et al. Mutational spectrum of breast cancer susceptibility genes among women ascertained in a cancer risk clinic in Northeast Brazil. Breast Cancer Res Treat [Internet]. 2022 Jun 30 [cited 2022 May 19];193(2):485. Available from: /pmc/articles/PMC9090684/

10. Amanda de Araújo Rocha, Denise Corrêa Benzaquem, Cleiton Fantin. Identification of Germinal Mutations in Eight Exons of the BRCA1 Gene in Breast Cancer Patients in the State of Amazonas, Using Direct Sequencing. Journal of Pharmacy and Pharmacology [Internet]. 2020 Oct 28 [cited 2021 Apr 22];8(11). Available from: http://www.davidpublisher.com/index.php/Home/Article/index?id=44062.html

11. Vidal AF, Ferraz RS, El-Husny A, Silva CS, Vinasco-Sandoval T, Magalhães L, et al. Comprehensive analysis of germline mutations in northern Brazil: a panel of 16 genes for hereditary cancer-predisposing syndrome investigation. BMC Cancer [Internet]. 2021 Dec 1 [cited 2022 Oct 25];21(1). Available from: https://pubmed.ncbi.nlm.nih.gov/33827469/

12. Friedman LS, Ostermeyer EA, Szabo CI, Dowd P, Lynch ED, Rowell SE, et al. Confirmation of BRCA1 by analysis of germline mutations linked to breast and ovarian cancer in ten families. Nat Genet [Internet]. 1994 Dec;8(4):399–404. Available from: https://www.nature.com/articles/ng1294-399

13. Alemar B, Gregório C, Herzog J, Bittar CM, Brinckmann Oliveira Netto C, Artigalas O, et al. BRCA1 and BRCA2 mutational profile and prevalence in hereditary breast and ovarian cancer (HBOC) probands from Southern Brazil: Are international testing criteria appropriate for this specific population? PLoS One. 2017;12(11).

14. Bandeira G, Rocha K, Lazar M, Ezquina S, Yamamoto G, Varela M, et al. Germline variants of Brazilian women with breast cancer and detection of a novel pathogenic ATM deletion in early-onset breast cancer. Breast Cancer [Internet]. 2021 Mar 1 [cited 2022 Oct 25];28(2):346–54. Available from: https://pubmed.ncbi.nlm.nih.gov/32986223/

15. Silva FC, Lisboa BC, Figueiredo MC, Torrezan GT, Santos ÉM, Krepischi AC, et al. Hereditary breast and ovarian cancer: assessment of point mutations and copy number variations in Brazilian patients. BMC Med Genet [Internet]. 2014 Dec 15 [cited 2022 Mar 18];15(1):55. Available from: https://bmcmedgenet.biomedcentral.com/articles/10.1186/1471-2350-15-55

16. Fernandes GC, Michelli RAD, Galvão HCR, Paula AE, Pereira R, Andrade CE, et al. Prevalence of BRCA1/BRCA2 mutations in a Brazilian population sample at-risk for hereditary breast cancer and characterization of its genetic ancestry. Oncotarget. 2016;7(49).

17. Felicio PS, Alemar B, Coelho AS, Berardinelli GN, Melendez ME, Lengert AVH, et al. Screening and characterization of BRCA2 c.156_157insAlu in Brazil: Results from 1380 individuals from the South and Southeast. Cancer Genet [Internet]. 2018 Dec;228–229:93–7. Available from: https://linkinghub.elsevier.com/retrieve/pii/S2210776218300590

18. Pena SDJ, Santos FR, Tarazona‐Santos E. Genetic admixture in Brazil. Am J Med Genet C Semin Med Genet [Internet]. 2020 Dec 18 [cited 2022 Jun 6];184(4):928–38. Available from: https://onlinelibrary.wiley.com/doi/10.1002/ajmg.c.31853

19. Heather JM, Chain B. The sequence of sequencers: The history of sequencing DNA. Genomics [Internet]. 2016 Jan 1;107(1):1–8. Available from: https://linkinghub.elsevier.com/retrieve/pii/S0888754315300410

20. Palmero EI, Carraro DM, Alemar B, Moreira MAM, Ribeiro-dos-Santos Â, Abe-Sandes K, et al. The germline mutational landscape of BRCA1 and BRCA2 in Brazil. Sci Rep [Internet]. 2018 Jun 15 [cited 2019 Dec 16];8(1):9188. Available from: https://www.nature.com/articles/s41598-018-27315-2

21. Leite TKM, Fonseca RMC, de França NM, Parra EJ, Pereira RW. Genomic ancestry, self-reported “color” and quantitative measures of skin pigmentation in Brazilian admixed siblings. PLoS One. 2011 Nov 2;6(11).

22. Telles EE. Racial ambiguity among the Brazilian population. Ethn Racial Stud [Internet]. 2002 Jan;25(3):415–41. Available from: http://www.tandfonline.com/doi/abs/10.1080/01419870252932133

23. Provenzano E, Ulaner GA, Chin SF. Molecular Classification of Breast Cancer. PET Clin [Internet]. 2018;13(3):325–38. Available from: https://doi.org/10.1016/j.cpet.2018.02.004

24. Nascimento RG do, Otoni KM. Histological and molecular classification of breast cancer: what do we know? Mastology. 2020;30.

25. Yoshida R. Hereditary breast and ovarian cancer (HBOC): review of its molecular characteristics, screening, treatment, and prognosis. Breast Cancer [Internet]. 2021 [cited 2022 Feb 19];28:1167–80. Available from: https://doi.org/10.1007/s12282-020-01148-2

26. Spurdle AB, Healey S, Devereau A, Hogervorst FBL, Monteiro ANA, Nathanson KL, et al. ENIGMA-evidence-based network for the interpretation of germline mutant alleles: An international initiative to evaluate risk and clinical significance associated with sequence variation in BRCA1 and BRCA2 genes. Hum Mutat. 2012 Jan;33(1):2–7.

27. Lee A, Moon BI, Kim TH. BRCA1/BRCA2 pathogenic variant breast cancer: Treatment and prevention strategies. Vol. 40, Annals of Laboratory Medicine. Seoul National University, Institute for Cognitive Science; 2020. p. 114–21.

28. Petrova D, Cruz M, Sánchez MJ. BRCA1/2 testing for genetic susceptibility to cancer after 25 years: A scoping review and a primer on ethical implications. The Breast [Internet]. 2022 Feb [cited 2022 Jan 17];61:66–76. Available from: https://linkinghub.elsevier.com/retrieve/pii/S0960977621010110

29. Foulkes WD. The ten genes for breast (and ovarian) cancer susceptibility. Nat Rev Clin Oncol [Internet]. 2021 May 10;18(5):259–60. Available from: http://www.nature.com/articles/s41571-021-00491-3

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Publicado

2026-07-17

Cómo citar

Ferreira, J. F. B., da Silva, I. L. V., de Lima, C. C. A., Brito, D. V., & Rezende, C. F. (2026). Absence of allelic variants in the BRCA1 gene of northern Brazilian breast cancer patients who met criteria for hereditary predisposition: a transversal study. Revista Contexto & Saúde, 26(51), e16745. https://doi.org/10.21527/2176-7114.2026.51.16745

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