title: Vitrification at Day3 stage appears not to affect the methylation status of H19/IGF2 differentially methylated region of in vitro produced human blastocysts.
abstract: One of the most widely used assisted reproductive technology (ART) is vitrification. The aim of this study is to evaluate DNA methylation of H19/IGF2 differentially methylation region (DMR) in in vitro produced human blastocysts derived from non-vitrified and vitrified day3 embryos. Day3 embryos derived from ICSI cycles from fertile couples referring for family balancing program were either biopsied or vitrified/warmed and subsequently biopsied. Following biopsy, embryos were cultured to day 5. Day5 blastocysts with desired sex were transferred or vitrified for future use. Blastocysts with un-desired sex were donated for research. The assessment of the embryos was performed in two non-vitrified and vitrified groups. Methylation level of H19/IGF2 DMR was analysed by bisulfite conversion and sequencing at 18 CpG sites (CpGs) located in this region. Results showed that the overall methylated CpGs percentages of this region in the vitrified and non-vitrified groups were 35.3% ± 3.6 and 38.27 ± 4.1%, respectively. The difference between the two groups was not significant. Vitrification of day3 embryo appears to have no adverse effect on DNA methylation status of H19/IGF2 DMR of embryos cultured in vitro to blastocyst stage. These data may have implications for performing frozen embryo cycles transfer instead of fresh embryo transfer cycles, owing to the naturally synchronized uterus and subsequently improved endometrial receptivity in frozen embryo transfer instead of imbalanced hormonal milieu in fresh embryo transfer cycles.
authors: Department of Anatomy, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran.
authors: Marzieh
authors: M
authors: Derakhshan-Horeh
authors: Department of Anatomy, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran. Electronic address: abolhasf@sina.tums.ac.ir.
authors: Farid
authors: F
authors: Abolhassani
authors: Department of Reproductive Biotechnology, Reproductive Biomedicine Research Center, Royan Institute for Biotechnology, ACECR, Isfahan, Iran.
authors: Farnoosh
authors: F
authors: Jafarpour
authors: Department of Endocrinology and Female Infertility, Reproductive Biomedicine Research Centre, Royan Institute for Reproductive Biomedicine, ACECR, Tehran, Iran; Department of Obstetrics and Gynecology, Faculty of Medicine, Tehran University of Medical Sciences, Tehran, Iran.
authors: Ashraf
authors: A
authors: Moini
authors: Department of Cellular Biotechnology, Cell Science Research Center, Royan Institute for Biotechnology, ACECR, Isfahan, Iran.
authors: Khadijeh
authors: K
authors: Karbalaie
authors: Department of Reproductive Biotechnology, Reproductive Biomedicine Research Center, Royan Institute for Biotechnology, ACECR, Isfahan, Iran.
authors: Sayyed Morteza
authors: SM
authors: Hosseini
authors: Department of Reproductive Biotechnology, Reproductive Biomedicine Research Center, Royan Institute for Biotechnology, ACECR, Isfahan, Iran; Department of Cellular Biotechnology, Cell Science Research Center, Royan Institute for Biotechnology, ACECR, Isfahan, Iran; Isfahan Fertility & Infertility Center, Isfahan, Iran. Electronic address: mh.nasr-esfahani@royaninstitute.org.
authors: Mohammad Hossein
authors: MH
authors: Nasr-Esfahani
mesh_terms: D000818:Animals; D001755:Blastocyst / Q000166:cytology / Q000378:metabolism*; D015925:Cryopreservation / Q000379:methods*; D019175:DNA Methylation / Q000235:genetics*; D004624:Embryo Transfer; D005260:Female; D018392:Genomic Imprinting / Q000235:genetics*; D006801:Humans; D027724:Reproductive Techniques, Assisted; D058989:Vitrification
keywords: DNA methylation; H19/IGF2 DMR; In vitro produced human blastocyst; Vitrification