Screening of Variants in the Transcript Profile of Eutopic Endometrium from Infertile Women with Endometriosis during the Implantation Window

Abstract Objective Abnormalities in the eutopic endometrium of women with endometriosis may be related to disease-associated infertility. Although previous RNA-sequencing analysis did not show differential expression in endometrial transcripts of endometriosis patients, other molecular alterations could impact protein synthesis and endometrial receptivity. Our aim was to screen for functional mutations in the transcripts of eutopic endometria of infertile women with endometriosis and controls during the implantation window. Methods Data from RNA-Sequencing of endometrial biopsies collected during the implantation window from 17 patients (6 infertile women with endometriosis, 6 infertile controls, 5 fertile controls) were analyzed for variant discovery and identification of functional mutations. A targeted study of the alterations found was performed to understand the data into disease’s context. Results None of the variants identified was common to other samples within the same group, and no mutation was repeated among patients with endometriosis, infertile and fertile controls. In the endometriosis group, nine predicted deleterious mutations were identified, but only one was previously associated to a clinical condition with no endometrial impact. When crossing the mutated genes with the descriptors endometriosis and/or endometrium, the gene CMKLR1 was associated either with inflammatory response in endometriosis or with endometrial processes for pregnancy establishment. Conclusion Despite no pattern of mutation having been found, we ponder the small sample size and the analysis on RNA-sequencing data. Considering the purpose of the study of screening and the importance of the CMKLR1 gene on endometrial

摘要 目的 子宫内膜异位症患者在位子宫内膜的异常改变，可能与该疾病相关的不孕症有关。既往RNA测序（RNA-Sequencing）分析未发现子宫内膜异位症患者子宫内膜转录本存在差异表达，但其他分子改变可能影响蛋白质合成与子宫内膜容受性。本研究旨在筛选不孕症合并子宫内膜异位症患者与对照组在种植窗（implantation window）时期在位子宫内膜转录本中的功能突变。方法 对17名受试者（6名不孕症合并子宫内膜异位症患者、6名不孕症对照组受试者、5名可生育对照组受试者）在种植窗时期采集的子宫内膜活检样本的RNA测序数据进行分析，以开展变异检测与功能突变鉴定；并针对发现的异常改变开展靶向研究，以明确其在疾病背景中的意义。结果 本研究鉴定出的变异均未在同组其他样本中出现，且子宫内膜异位症患者、不孕症对照组与可生育对照组受试者之间未出现重复突变。子宫内膜异位症组共鉴定出9个预测为有害的突变，但仅1个既往被报道与临床病症相关，且未对子宫内膜产生影响。将突变基因与子宫内膜异位症和/或子宫内膜相关的描述信息进行交叉比对后发现，CMKLR1基因既与子宫内膜异位症的炎症反应相关，也与妊娠建立过程中的子宫内膜生理过程有关。结论 尽管未发现突变模式，但我们考虑到本研究样本量较小，且分析基于RNA测序数据。结合本研究的筛查目的，以及CMKLR1基因在子宫内膜