Stork Fertility Center, Stork Ladies Clinic, Hsinchu, Taiwan.
Graduate Institute of Clinical Medicine, National Taiwan University and College of Medicine, Taipei, Taiwan.
Front Endocrinol (Lausanne). 2023 Jan 4;13:1066530. doi: 10.3389/fendo.2022.1066530. eCollection 2022.
To investigate whether the mitochondrial DNA (mtDNA) content of a single biopsy at trophoblast correlates with the developmental potential and reproductive outcomes of blastocyst.
A retrospective analysis applied the dataset of 1,675 embryos with preimplantation genetic testing for aneuploidy (PGT-A) from 1,305 individuals, and 1,383 embryos involved cryotransfers of single euploid embryo between January 2015 and December 2019. The studied cohort was divided for algorithm establishment on the NGS platform (n=40), correlation of biological features (n=1,635), and correlation of reproductive outcomes (n=1,340). Of the algorithm derived from the NGS platform, the reliability and repeatability were validated qPCR assay and inter-run controls, respectively. Of the correlation across biological features, stratification analyses were applied to evaluate the effect from a single contributor. Eventually, the correlation between the mtDNA ratios and reproductive outcomes was adjusted according to the significant effector(s).
The mtDNA ratios showed statistically different between embryos with different days of blastocyst formation ([Day 5]: 1.06 vs. [Day 6]: 0.66, p=0.021), and between embryos with different expansion stages ([Expansion 5]: 1.05 vs. [Expansion 6]: 0.49, p=0.012). None or weakly correlated with the maternal age, morphology, ploidy, and gender. Analyzed by the different days of blastocyst formation with fixed expansion score as 5 in the euploid single embryo transfers (eSET), the day 6 eSET showed significantly lower reduced mtDNA ratio (n=139) in failure groups of fetal heartbeat (p=0.004), ongoing pregnancy (p=0.007), and live birth (p=0.01); however, no correlation between mtDNA ratios and pregnancy outcomes was observed in the day 5 eSET (n=1,201).
The study first demonstrated that mtDNA ratio was dependent on the days of blastocyst formation while expansion stage was fixed. Lower mtDNA ratios were observed in the day 6 eSET with adverse outcomes. The present stratification analyses reveal that the timeline of embryo is an important covariate to the mtDNA content.
探讨单个滋养层活检中的线粒体 DNA（mtDNA）含量是否与囊胚的发育潜能和生殖结局相关。
回顾性分析了来自 1305 名个体的 1675 个胚胎的植入前遗传学检测非整倍体（PGT-A）数据集，以及 2015 年 1 月至 2019 年 12 月期间单个整倍体胚胎冷冻转移的 1383 个胚胎。该研究队列分为基于 NGS 平台的算法建立（n=40）、生物学特征相关性（n=1635）和生殖结局相关性（n=1340）。从 NGS 平台得出的算法分别通过 qPCR 测定和运行间对照进行了可靠性和可重复性验证。在生物学特征相关性方面，进行了分层分析，以评估单个供体的影响。最终，根据显著效应物（s）调整 mtDNA 比与生殖结局之间的相关性。
在不同囊胚形成天数的胚胎之间（[第 5 天]：1.06 比 [第 6 天]：0.66，p=0.021），以及在不同扩张阶段的胚胎之间（[扩张 5 期]：1.05 比 [扩张 6 期]：0.49，p=0.012），mtDNA 比值存在统计学差异。与母体年龄、形态、倍性和性别无关或相关性较弱。在整倍体单胚胎转移（eSET）中以固定扩张评分 5 分析不同囊胚形成天数，第 6 天 eSET 的胎心停止（p=0.004）、持续妊娠（p=0.007）和活产（p=0.01）失败组的 mtDNA 比值明显降低，但在第 5 天 eSET（n=1201）中未观察到 mtDNA 比值与妊娠结局之间存在相关性。
本研究首次表明，mtDNA 比值取决于囊胚形成的天数，而扩张阶段是固定的。在不良结局的第 6 天 eSET 中观察到较低的 mtDNA 比值。本分层分析表明，胚胎的时间线是 mtDNA 含量的一个重要协变量。
