Novel BRCA2 pathogenic genotype and breast cancer phenotype discordance in monozygotic triplets

Eur J Med Genet. 2020 Apr;63(4):103771. doi: 10.1016/j.ejmg.2019.103771. Epub 2019 Sep 26.

Abstract

BRCA1/2 genes with high-penetrance are tumor suppressor and tumor susceptibility genes that play important roles in the homologous recombination mechanism in DNA repair and increase breast cancer risk. Variants in BRCA1 or BRCA2 are the main causes of familial and early-onset breast cancer. This study investigated pathogenic variant belonging to the BRCA2 gene splice region in monozygotic triplets. A 44-year-old woman was diagnosed with breast cancer when she was 32 years old. Her monozygotic sister had a history of breast cancer. No malignancy was detected in the third one of the monozygotic triplets. Sanger sequencing was used to evaluate the BRCA1/2 gene status of the patient and family members. It was figured out that they had the same genetic variant, a heterozygous germ-line splice region variant (c.7008-1G > C) in the BRCA2 gene. This novel splice region variant may be a new pathogenic variant of the BRCA2 gene. Its association with breast cancers needs to be further verified in more patient cases.

Keywords: A novel variant; BRCA; Breast cancer; Pathogenic.

Publication types

  • Case Reports

MeSH terms

  • Adult
  • Alternative Splicing*
  • BRCA2 Protein / genetics*
  • Breast Neoplasms / genetics*
  • Breast Neoplasms / pathology*
  • Female
  • Genetic Predisposition to Disease*
  • Genotype
  • Germ-Line Mutation*
  • Humans
  • Pedigree
  • Penetrance
  • Phenotype
  • Triplets / genetics*

Substances

  • BRCA2 Protein
  • BRCA2 protein, human