Susceptibility to breast cancer and intron 3 Ins/Del genetic polymorphism of DNA double-strand break repair gene XRCC4

• Main Authors: Saadat Mostafa, Saadat Shekoofeh
• Format: Article
• Language: English
• Published: Society of Medical Biochemists of Serbia, Belgrade 2015-01-01
• Series: Journal of Medical Biochemistry
• Subjects: age at diagnosis; breast cancer; polymorphism; susceptibility; xrcc4
• Online Access: https://scindeks-clanci.ceon.rs/data/pdf/1452-8258/2015/1452-82581504409S.pdf
• ISSN: 1452-8258; 1452-8266

Background: Since genetic variations in X-ray cross-complementing group 4 (XRCC4; OMIM: 194363) repair gene might be associated with a reduction in cellular DNA repair capacity, it is hypothesized that XRCC4 Ins/Del (I/D) polymorphism (in intron 3 of the gene; rs28360071) may be a risk factor for breast cancer. Therefore, the present casecontrol study was carried out. Methods: The present case-control study included 407 females with breast cancer and a total of 394 healthy females from the general population matched with patients according to age. Genotypic analysis for the XRCC4 I/D polymorphism was performed by PCR. In order to investigate the effect of XRCC4 I/D polymorphism on age at diagnosis of breast cancer, the Kaplan-Meier survival analysis and the Cox proportional hazards regression model were used. Results: Based on the present case-control study, the ID (OR = 0.95, 95% CI: 0.69-1.31, P = 0.781) and DD (OR = 1.24, 95% CI: 0.84-1.83, P = 0.274) genotypes were not associated with breast cancer risk compared with the II genotype. Based on the Cox regression model, there was significant association between genotypes of I/D polymorphism and age at diagnosis of breast cancer (ID + DD vs II; HR = 0.79, 95% CI: 0.64-0.98, P = 0.036). Conclusion: Although there was no significant association between XRCC4 I/D polymorphism and risk of breast cancer, patients having the II genotype have lower age at diagnosis in comparison with patients having ID + DD genotypes.