Association between gene polymorphism of GRK5 and breast cancer risk in Chinese population

Potential influences of GRK5 polymorphism on cancer risks have been reported. This study aimed to explore the distribution of GRK5 genotypes and alleles in Chinese breast cancer (BCa) patients, and to analyze the association between GRK5 and BCa risk.

Blood samples were collected from 412 BCa patients and 533 healthy individuals for isolating genomic DNA. GRK5 polymorphisms of Gln41Leu A > T and Arg304His G > A, and their alleles were detected using PCR-RFLP. Their influences on BCa susceptibility and pathological indexes were analyzed using Logistic regression model.

No significant differences in age, body mass index (BMI) and smoking status were found between BCa patients and healthy persons, while significant differences were detected in drinking status, family history of cancer, hypertension and diabetes. GRK5Gln41Leu A > T and its allele frequency distribution were correlated to BCa susceptibility, while GRK5 Arg304His G > A was not. Higher risks of GRK5 Gln41Leu A > T and Arg304His G > A indicated a higher susceptibility to BCa. Compared with people carrying 0-1 risk allele, those carrying 2-4 risk alleles of GRK5 Gln41Leu A > T and Arg304His G > A of had a higher susceptibility to BCa, manifesting as worse tumor staging and grading, and higher rates of estrogen receptor (ER) (-), progesterone receptor (PR) (-) and HER2 (-).

Gln41Leu A > T and Arg304His G > A fusion gene polymorphisms of GRK5 are vital genetic susceptibility genes to BCa. Our findings require to be validated in a multicenter study with a high-quality large sample size.