Investigation on MDR1 gene polymorphisms and its relationship with breast cancer risk factors in Chinese women.

The human multidrug resistance 1 gene (MDR1) is an important candidate gene influencing the susceptibility to various diseases, including breast cancer. The object of this study was to investigate on MDR1 gene polymorphisms and its relationship with the susceptibility to breast cancer. A total of 271 patients with breast cancer and 225 healthy controls were enrolled in this study. Data about the risk factors for breast cancer were collected using questionnaires. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and DNA sequencing methods were used to investigate the c.3073A > C polymorphisms. We observed no significant differences in the allelic and genotypic frequencies of c.3073A > C polymorphisms between patients and control subjects. Furthermore, there were no significant differences about the distribution of the breast cancer patients' risk factors among AA, AC and CC genotype. Results from this study suggested that c.3073A > C polymorphism was not associated with the susceptibility to breast cancer in the studied population. Future studies evaluating the association between c.3073A > C variant and breast cancer risks are essential to reach to more reliable results on larger populations.