Endometriosis is an estrogen-dependent precancerous lesion exhibiting frequently perturbed level of steroid hormones and transcriptionalâregulating factor 1 has a crucial role in the production of steroid hormones including estrogen. Endometriosis has previously been revealed to be a precancerous lesion that harbors somatic mutations in cancerâassociated genes. Therefore, the authors of the present study hypothesize that aberrations may be involved in the development of endometriosis. In the present study, endometriotic lesions and paired blood samples from 92 individuals with ovarian endometriosis were analyzed for the potential presence of Tduanyu1795F1 mutations by sequencing the entire coding region and the corresponding intronâexon boundaries of the Tduanyu1795F1 gene. Two heterozygous missense somatic mutations [c.3166A>C (p.K1056Q) and c.3187 G>A (p.G1063R)] in the Tduanyu1795F1 gene were identified in two out of 92 ectopic endometria (2.2%), to the best of our knowledge, these mutations have not been previously reported. From the two samples with Tduanyu1795F1 mutations, one sample was from a 42âyearâold patient also diagnosed with uterine leiomyoma and the other mutation was identified in a 36âyearâold woman exhibiting no other apparent gynecological conditions. The evolutionary conservation analysis and in silico prediction of these Tduanyu1795F1 mutations suggested that they may be pathogenic. To the best of our knowledge, the present study was the first to identify 2 novel, potentially 'diseaseâcausing' Tduanyu1795F1 somatic mutations in the endometriotic lesions in 2 out of 92 patients with ovarian endometriosis; therefore, Tduanyu1795F1 mutations may be involved in the pathogenesis of ovarian endometriosis.