BRCA1 rs799917 and rs1799966 Variants and Breast Cancer Risk in Nigerian Women: A Case-Control Study With
Ogunniyi B Oluwabusayo1,2, Abimbola F Onyia1,2, Olutola E Olasehinde1,2
1Department of Biochemistry, Covenant University, Ota, Nigeria.
Cancer Control : Journal of the Moffitt Cancer Center
|July 16, 2026
Summary
BRCA1 gene variants rs799917 and rs1799966 are not linked to breast cancer risk in Nigerian women. Allele frequencies vary significantly across global populations, emphasizing the role of genetic diversity in cancer susceptibility.
Area of Science:
- Genetics
- Oncology
- Population Genetics
Background:
- BRCA1 gene mutations are linked to hereditary breast cancer.
- Specific BRCA1 single nucleotide polymorphisms (SNPs), rs799917 and rs1799966, have shown inconsistent associations with breast cancer risk globally.
- The prevalence and clinical significance of these BRCA1 SNPs in Nigerian populations are not well-established.
Purpose of the Study:
- To investigate the association between BRCA1 SNPs rs799917 and rs1799966 and breast cancer risk in Nigerian women.
- To analyze allele frequency variations of these SNPs across different global populations.
Main Methods:
- A prospective case-control study involving 379 breast cancer cases and 196 controls.
- Genotyping of BRCA1 rs799917 (A/G) and rs1799966 (C/T) using TaqMan real-time PCR.
- Statistical analysis using logistic regression and meta-analysis of global allele frequency data from dbSNP.
Main Results:
- No statistically significant association was found between BRCA1 variants rs799917 and rs1799966 and breast cancer risk in the Nigerian cohort.
- Genotype distributions were similar between breast cancer cases and controls.
- Meta-analysis revealed substantial inter-population differences in allele frequencies, with Africans exhibiting distinct patterns for both SNPs compared to Europeans and Asians.
Conclusions:
- BRCA1 variants rs799917 and rs1799966 do not appear to influence breast cancer susceptibility in the studied Nigerian population.
- Significant global variations in allele frequencies highlight the importance of considering genetic diversity in breast cancer risk assessments.
- Further research is needed to understand the complex interplay of genetic factors and breast cancer risk across diverse ethnicities.
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