Evaluation of KRAS Gene Expression and LCS6 Variant in Genomic and Cell-Free

Since the activation of KRAS results in de novo endometriosis in mice, KRAS is regarded as a crucial gene in ectopic endometrial implantation. Recently, it has been reported that 31 % of women with endometriosis have KRAS let-7 complementary binding site 6 single-nucleotide polymorphism (LCS6 SNP). This study addresses the correlation between KRAS LCS6 SNP and endometriosis in a case–control study. To detect probable somatic mutation in ectopic endometrial tissue, we evaluated LCS6 SNP in cell-free DNA samples. Quantitative real-time reverse transcription-polymerase chain reaction was performed to determine the expres-sion of KRAS transcripts in eutopic endometrial tissue. Our results suggest that the variant is not associated with the development of endometriosis in Iranian women. We observed higher levels of KRAS messenger RNA (mRNA) expression in eutopic endo-metrium of patients with endometriosis compared to controls. Although, the KRAS LCS6 is neither constitutional nor somatic biomarker for endometriosis, increased expression ratio of KRAS mRNA indicates its role in the implantation of endometrial tissue outside the uterine cavity.