mtDNA dynamics between cleavage-stage embryos and blastocysts
- 86 Downloads
The aim was to evaluate mtDNA content and its dynamics in euploid and aneuploid embryos from cleavage to blastocyst stage following consecutive biopsies. The effect of female age on mtDNA content was evaluated by comparing reproductively younger (≤ 37 years) with older (> 37 years) women.
A retrospective single-centre descriptive study was performed between August 2016 and January 2017. Forty patients, with 112 embryos, undergoing preimplantation genetic testing for aneuploidies (PGT-A) by next-generation sequencing (NGS) were included. Embryos that reached the blastocyst stage and were not selected for fresh embryo transfer were included following consecutive biopsies of a single blastomere on day 3 and trophectoderm biopsy of day 5 blastocysts.
Cleavage-stage mtDNA was significantly lower in fast cleaving embryos (p = 0.016). Based on the concordance between day 3 and day 5 biopsies, a difference was identified in blastocyst mtDNA content between groups (p = 0.019); true euploid blastocysts presented a lower mtDNA content. No association was identified between cleavage-stage mtDNA content and ploidy status (OR 1.008 [0.981–1.036], p = 0.565) nor between blastocyst mtDNA content and ploidy outcome (OR 0.954 [0.898–1.014], p = 0.129). No difference was found when comparing mtDNA content and ploidy outcome between the two reproductive age groups (p = 0.505 (cleavage stage) and p = 0.774 (blastocyst)).
Mitochondrial DNA content of cleavage-stage embryos and blastocysts is unable to predict ploidy status. Subgroup analysis based on ploidy concordance between day 3 and day 5 revealed a significantly lower mtDNA content for true euploid blastocysts. Reproductive ageing does not affect mtDNA content.
KeywordsCleavage-stage embryo Blastocyst mtDNA PGT-A NGS
Compliance with ethical standards
Approval for this study was obtained from the local Ethics Committee of IVIRMA Middle East Fertility Clinic, Abu Dhabi, UAE (Research Ethics Committee IVI-MEREF010/2017/REFA009). All patients signed a consent form allowing additional trophectoderm biopsy of supernumerary euploid and aneuploid embryos not selected for transfer.
- 8.Desquiret-Dumas Desquiret-Dumas V, Clément A, Seegers V, Boucret L, Ferré-L’Hotellier V, Bouet PE, et al. The mitochondrial DNA content of cumulus granulosa cells is linked to embryo quality. Hum Reprod. 2017;32(3):607–14.Google Scholar
- 10.Cecchino GN, Garcia-Velasco JA. Mitochondrial DNA copy number as a predictor of embryo viability. Fertil Steril. 2018:0015–282.Google Scholar
- 28.Treff NR, Zhan Y, Tao X, Olcha M, Han M, Rajchel J, et al. Levels of trophectoderm mitochondrial DNA do not predict the reproductive potential of sibling embryos. Hum Reprod. 2017;32(4):954–62.Google Scholar
- 33.Phillips NR, Sprouse ML, Roby RK. Simultaneous quantification of mitochondrial DNA copy number deletion ratio: a multiplex real-time PCR assay. SciRep. 2014;4:3887.Google Scholar
- 43.Capalbo A, Wright G, Elliott T, Ubaldi FM, Rienzi L, Nagy ZP. FISH reanalysis of inner cell mass and trophectoderm samples of previously array-CGH screened blastocysts shows high accuracy of diagnosis and no major diagnostic impact of mosaicism at the blastocyst stage. Hum Reprod. 2013;28:2298–307.CrossRefGoogle Scholar