Quantitative Expression of BAG1, BAX and BCL-2 genes in Human Embryos with Different Fragmentation Grades Derived from ART

Abstract

Objective: The purpose of this study was to evaluate the quantitative expressions ofBAG1, BAX and BCL-2 in human embryos with different fragmentation grades as derivedfrom assisted reproduction technology (ART).Materials and Methods: Fragmented and normal human 8-cell embryos were scoredaccording to the degree of fragmentation with an inverted microscope and divided intofour grades (grade І: no or minimal fragmentation (25% fragmentation and grade ІV: apoptotic inducedembryos with actinomycin D). In this study, TUNEL labeling was initially used todetect apoptosis, and then revers transcription polymerase chain reaction (RT-PCR) andquantitative PCR were used to define the quantitative expressions of experimental genesin human embryos with different fragmentation grades.Results: The results of TUNEL labeling showed that embryos with higher fragmentationhad a high number of apoptotic bodies. The results of RT-PCR and q-PCR analysesshowed a significantly decreased amount of BAGI transcript expression from group I togroup IV. The highest expression of BAX gene was observed in group II, however, thetranscript of BCL-2 gene was not observed in any of the experimental groups. The effectof actinomycin D on transcript expression amounts of experimental genes in apoptoticinduced embryos (group IV) compared to control embryos (group I) showed a significantdecrease.Conclusion: mRNA expression of BAG1 gene can be used as a good marker to detectapoptosis in human embryos. However, the transcript of BCL-2 gene does not play a rolein the detection of apoptosis in human embryos at the 8-cell stage.

Keywords

• Human Embryo
• Fragmentation
• Apoptotic Genes
• Actinomycin D
• TUNEL