Methylation Status of H19/IGF2 Differentially Methylated Region in in vitro Human Blastocysts Donated by Healthy Couples

Authors
Marzieh Derakhshan-Horeh 1
Farid Abolhassani 1
Farnoosh Jafarpour 2
Ashraf Moini 3
Khadijeh Karbalaie 4
Sayyed Morteza Hosseini 2
Somayyeh Ostadhosseini 2
Mohammad Hossein Nasr-Esfahani* 2
1 Department of Anatomy, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
2 Department of Reproductive Biotechnology, Reproductive Biomedicine Research Center, Royan Institute for Biotechnology, Academic Center for Education, Culture and Research (ACECR), Isfahan, Iran
3 Department of Endocrinology and Female Infertility, Reproductive Biomedicine Research Centre, Royan Institute for Reproductive Biomedicine, ACECR, Tehran, Iran
4 Department of Cellular Biotechnology, Cell Science Research Center, Royan Institute for Biotechnology, ACECR, Isfahan, Iran
10.18869/acadpub.ibj.21.1.16
Abstract
Backgrund: Imprinted genes are a unique subset of few genes, which have been differentially methylated region (DMR) in a parental origin-dependent manner during gametogenesis, and these genes are highly protected during pre-implantation epigenetic reprogramming. Several studies heve shown that the particular vulnerability of imprinting genes during suboptimal pre- and peri-conception microenvironments often occur by assisted reproduction techniques (ART). This study investigated the methylation status of H19/IGF2 DMR at high-quality expanding/expanded human blastocysts donated by healthy individuals to evaluate the risks linked to ART. Method: Methylation levels of H19/IGF2 DMR were analyzed by bisulfite conversion and sequencing at 18 CpG sites (CpGs) located in this region. Result: Results showed that the overall percentage of methylated CpGs and the proportion of hyper-methylated clones of H19/IGF2 DMR in analyzed blastocysts were 37.85±4.87% and 43.75±5.1%, respectively. For validation of our technique, the corresponding methylation levels of peripheral human lymphocytes were defined (49.52±1.86% and 50%, respectively). Conclusion: Considering the absence of in vivo produced human embryos, it is not possible to conclude that the methylation found in H19/IGF2 DMR is actually normal or abnormal. Regarding the possible risks associated with ART, the procedures should be optimized in order to at least reduce some of the epigenetic risks.
Keywords
Blastocyst
Genomic imprinting
H19/IGF2 DMR
human
Reproductive technique