Age at onset of bilateral breast cancer, the presence of hereditary BRCA1, BRCA2, CHEK2 gene mutations and positive family history of cancer.
BACKGROUND
Our research focused on the relations between the age at onset of bilateral breast cancer and the prevalence of selected hereditary BRCA1, BRCA2 and CHEK2 gene mutations with reference to their positive family history of cancer.


METHODS
The DNA of peripheral blood lymphocytes of patients was examined for the presence of selected hereditary mutations in the BRCA1, BRCA2 and CHEK2 genes, using molecular biology techniques. The family history of neoplasms was also analyzed.


RESULTS
The following mutations in the BRCA1 gene were identified: 185delAG, C61G, 5382insC, 3875 del11ins7, and R1751X. In the BRCA2 gene, the 9631delC and A9599T mutations were found. In the CHEK2 gene, the 1100delC and I157T mutations were identified. BRCA1/2 gene mutations were identified in 19.4% of patients and CHEK2 gene mutations in 7%.


CONCLUSIONS
It was shown that the presence of the mutations in the BRCA1/2 genes among patients with bilateral breast cancer is associated with an earlier occurrence of the first and the second breast cancer than in patients without hereditary mutations in these genes (a difference of 7.2-8.4 years). In patients with CHEK2 gene mutations, breast cancer occurred 2.1-3.8 years earlier than in patients without mutations in the CHEK2 gene.
Department of Endocrinology, Maria Sklodowska-Curie Memorial Cancer Center and Institute of Oncology, Warsaw, Poland. eskasko@coi.waw.pl
Elzbieta
E
Skasko
Anna
A
Kluska
Anna
A
Niwińska
Ewa
E
Kwiatkowska
Aneta
A
Bałabas
Magdalena
M
Piatkowska
Michalina
M
Dabrowska
Dorota
D
Nowakowska
Tadeusz
T
Pieńkowski
D017668:Age of Onset; D051017:Apoptosis Regulatory Proteins; D024682:BRCA2 Protein / Q000235:genetics*; D001943:Breast Neoplasms / Q000453:epidemiology* / Q000235:genetics*; D064447:Checkpoint Kinase 2; D005190:Family; D005260:Female; D020022:Genetic Predisposition to Disease / Q000453:epidemiology / Q000235:genetics; D006801:Humans; D015994:Incidence; D008875:Middle Aged; D009154:Mutation; D011044:Poland / Q000453:epidemiology; D020641:Polymorphism, Single Nucleotide / Q000235:genetics*; D017346:Protein Serine-Threonine Kinases / Q000235:genetics*; D044767:Ubiquitin-Protein Ligases / Q000235:genetics*
D051017:Apoptosis Regulatory Proteins; C118024:BLID protein, human; D024682:BRCA2 Protein; C551750:BRCA2 protein, human; C111164:BRAP protein, human; D044767:Ubiquitin-Protein Ligases; D064447:Checkpoint Kinase 2; C578634:CHEK2 protein, human; D017346:Protein Serine-Threonine Kinases