浜谷 敏生

Abstract Objective To generate an effective embryo prediction model and identify a non-invasive evaluation method by analyzing microRNAs (miRNAs) in embryo culture medium. Design Analysis of microRNA profiles from spent culture medium of blastocysts with good morphology that did or did not result in pregnancy. Setting Clinical and experimental research. Patients Sixty patients who underwent thawed embryo transfer of blastocysts after intracytoplasmic sperm injection. Intervention(s) None. Main outcome measure(s) The association of miRNA abundance levels secreted by blastocysts in culture medium and implantation success. Results Our RNA sequencing analysis found a total of 53 differentially expressed miRNAs in the culture media of pregnancy and non-pregnancy groups. Twenty-one miRNAs were analyzed for their potential to predict implantation success. Eight miRNAs (hsa-miR-191-5p, hsa-miR-320a, hsa-miR-92a-3p, hsa-miR-509-3p, hsa-miR-378a-3p, hsa-miR-28-3p, hsa-miR-512-5p, and hsa-miR-181a-5p) were further extracted from the results of a logistic regression analysis of qPCR Ct values. A prediction model for high-quality blastocysts was generated using the eight miRNAs, with an average accuracy of 0.82 by 5-fold cross validation. Conclusion We isolated blastocyst miRNAs that may predict implantation success and created a model to predict viable embryos. Increasing the number of investigated cases and further studying the effect of each miRNA on embryonic development is needed to refine the miRNA-based predictive model.

副腎皮質過形成(congenital adrenal hyperplasia:CAH)およびAZF遺伝子の欠失は、いずれも非閉塞性無精子症(NOA)の原因となりうる遺伝子異常である。今回我々は、CAHとAZFc部分欠失を合併した男性不妊症の事例に対して、精巣内精子採取術(TESE)および顕微授精(ICSI)により妊娠に至った事例を経験したので報告する。症例は、41歳男性と38歳女性の夫婦である。夫はCAHと診断されステロイド補充療法が実施されたものの、射出精液中に運動精子が認められず、NOAが疑われた。染色体検査およびAZF遺伝子検査がなされた結果、AZFcの部分欠失を認めた。以上を踏まえてTESEおよびICSIにより妊娠が成立したが、児は子宮内胎児死亡に至った。CAHとAZF遺伝子欠失とを原因とするNOAの事例においてもTESEが有用であることが示唆された。(著者抄録)