BACH1 Ser919Pro variant and breast cancer risk

Area of Science:

• Genetics
• Oncology
• Molecular Biology

Background:

• BRCA1-associated C-terminal helicase 1 (BACH1) is a helicase protein interacting with BRCA1, a key gene in hereditary breast cancer.
• Previous studies identified rare BACH1 mutations in early-onset breast cancer patients.
• The role of BACH1 genetic variants in breast cancer susceptibility requires further investigation.

Purpose of the Study:

• To investigate whether BACH1 genetic variants contribute to breast cancer risk in the Finnish population.
• To evaluate the association of the common BACH1 Ser919Pro polymorphism with breast cancer risk.
• To assess the impact of BACH1 germline alterations on familial breast cancer.

Main Methods:

• Screening of the BACH1 gene for germline alterations in 43 Finnish BRCA1/2-negative breast cancer families.
• Genotyping of the BACH1 Ser919Pro polymorphism in 888 unselected breast cancer patients and 736 healthy controls.
• Further analysis of the Val193Ile variant in independent cohorts.

Main Results:

• Six BACH1 germline alterations were identified, but none were associated with cancer phenotype.
• The BACH1 Ser919-allele did not show an increased risk for breast cancer in Finnish individuals.
• No association was found between the BACH1 Ser919 variant and tumor characteristics, age at diagnosis, family history, or survival.

Conclusions:

• The BACH1 Ser919 variant is unlikely to be a breast cancer predisposition allele in the Finnish population.
• While rare BACH1 germline variants may have a minor role, their overall contribution to familial breast cancer appears marginal.
• Further research is needed to fully elucidate the role of BACH1 in breast cancer development.