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Background

The rates of infertility are growing in the world. In Vitro Fertilization (IVF) is one of the most common treatments, but the success rate is still low. Early embryogenesis is mainly dependent on the maternal mRNA which controls processes involved up to the period of Maternal Zygotic Transition (MZT). MZT occurs approximately at the 4-cell phase after which the embryonic genome is activated and in charge of development. Maternal mRNA seems to therefore control the implantation and hence the success rate of IVF. In an earlier study by this group, 4 cell stage porcine embryos were created by IVF, their RNA was extracted and sent to SciLifeLab for gene sequencing and bioinformatics. The bioinformatics created a library containing of more than 9900 genes which needed to be mapped toward the ones of fundamental importance for MZT. 

Aim

The aim of this project was to identify the genes most important for MZT from the library created by SciLifeLab and to validate their expression 4 cell embryos created by IVF. 

Method

Hence, this study was started by searching the literature to map the genes in the library to the ones crucial for MZT. New 4-cell porcine embryos were obtained by IVF, their RNA was extracted, and the concentration and purity of RNA was determined. Validation of expression of the genes was performed using RT-qPCR. 

Findings

Three genes were mentioned in most of the reviewed literature, namely SOX2, NANOG and POU5F1, all of which were detected in the mRNA of the samples analyzed. 

Conclusion

IVF embryos at 4 cell stage as a model and the methods used to study the genes expressed in these are applicable and useful for our upcoming studies to further characterize the maternal mRNA and its importance for early embryogenesis and success rate of IVF.