PhD defence: Qing Zhou

Maternal and paternal contribution to the development of human preimplantation embryos

Professor Søren Tvorup Christensen (Chair). Department of Biology, University of Copenhagen, Denmark
Professor Cizhong Jiang, Department of Biotechnology, Tongji University, China
Dr. Yuan Gao, National Research Center for Assisted Reproductive Technology & Reproductive Genetics, Sci.& Tech Park of Shandong University, China

Academic advisor
Karsten Kristiansen, Department of Biology, University of Copenhagen

Virtual defence in Zoom

Meeting ID: 617 7415 8453

About the thesis
Infertility is a critical component of reproductive health and remains a highly prevalent global condition. In many cases, couples with infertility may choose assisted reproductive technology (ART) to increase their chances of conception. However, an increasing application of ART treatment worldwide has also generated both scientific and public interest in its efficacy and safety. Since successful development of embryos in vitro is one of the key steps in ART and has a crucial influence on pregnancy outcome, an improved understanding of these processes will help us figure out the underlying mechanisms in ART failure due to poor embryonic development, especially for couples without normal embryos for transfer in several cycles.

This thesis presents the findings on the maternal and paternal contribution to human embryogenesis based on the dynamics of parental-of-origin sex chromosomes, as well as the effects of parental genetic background on embryonic development. The distinct activation and silencing of sex chromosomes result in an imbalanced dosage of gene expression, and thus, have potential effects on the sex-specific behavior of early embryos. The analysis of couples with recurrent poor embryonic development indicates that they are highly heterogeneous both phenotypically and genetically. These results will further knowledge within the ART field and possibly improve the treatment of infertility. In addition, the findings also enable potential application of whole genome sequencing to clinical diagnosis and it could contribute to improve genetic counseling of couples.