Study On The Clinical Relevance Of Mitochondrial DNA Content In Human Blastocysts

BackgroundThe embryo transfer outcome depends on many factors, such as the laboratory conditions, the patient’s age and Conditions of reproductive organs .Of course, the embryo quality is another important reason. It is said that insufficient energy produced by Mitochondria should take responsibility for both elderly transplant failure and unexplained embryo arrest[1,2].So, the problem that wether mtDNA can represent a novel biomarker with potential value for in vitro fertilisation (IVF) treatment has received much attention . Currently, some studies have shown that a high mtDNA copy number in euploid embryos is indicative of lower embryo viability and implantation[3,4].Meanwhile, some reports think that viable blastocysts did not contain significantly different mtDNA levels compared xwith unviable blastocysts[5].Therefore,our study will calculate the ratio of mtDNA to autosomal DNA copy number, with the hope that make a difference for the relationship between mitochondrial DNA content and results of embryo transfer.ObjectiveTo explore the relationship between the mitochondrial DNA content in human blastocysts and the result of embryo transfer.Methods1. Establish library about those wanted WGA samples;2. Sequencing via the CNV-seq which was at the basic of NGS;3. Calculate the ratio of mtDNA to autosomal DNA copy number via the RUPA analysis system.Results1. A total of 89 blastocyst aneuploid embryos derived from 77 patients from China. Single-embryo transfer in 65 patients and 10 patients with double-embryo transfer. A total of 190 blastocyst aneuploid embryos derived from 151 patients from USA. Single-embryo transfer in 112 patients and 39 patients with double-embryo transfer;2. In single-embryo transferered group, viable blastocysts did not contain significantly different mtDNA levels compared with unviable blastocysts ( P>0.05). This result do not change despite of stratified comparison of age and embryo grade;3. In double-embryo transferred group, the mtDNA content make no different between implanted and nonimplanted.ConclusionThe mtDNA content in human blastocysts are largely equal between implanted and nonimplanted.