Single nucleotide polymorphisms in the regulatory region of gonadotropin-releasing hormone receptor gene and breast cancer susceptibility.

It is known that exposure to estrogens affects the pathophysiology of breast cancer. The key role of gonadotropin-releasing hormone (GnRH) in the regulation of female steroid hormone metabolism raises the question of whether polymorphisms in its receptor, GnRHR, might influence breast cancer risk. To test this hypothesis, we analyzed three single nucleotide polymorphisms (SNPs) in the 5'-regulatory region of the GnRHR gene in a total of 565 women, 254 women with breast cancer and 311 women without any malignancy by allele-specific PCR. No significant differences were observed between the breast cancer and control group in terms of genotype, allele frequency or allele positivity. In contrast, different frequencies of the SNPs rs13138607, rs12644822 and rs3756159 were observed after sub-grouping the breast cancer cases according to tumor grading. Our data suggest a potential role of GnRHR gene polymorphisms in the development of breast cancer.