The Application Of Array Comparative Genomic Hybridization In Aneuploidy Screening Of Preimplanted Embryos

Objective: Using the technology of array comparative genomic hybridization (aCGH) to screen aneuploidy of human embryos before transfer. Establish a whole genome aneuploidy screening method to detect chromosomal abnormalities of single blastomeres.Methods:We chosed4cryopreserved embryos (E1、E2、E3、E4) which were normal fertilization of the patients who accepted in vitro fertilization treatment in the Tianjin Medical University General Hospital Reproductive Medicine Center. Couples voluntarily donate the frozen embryos for research and signed informed consent. We biopsied8blastomeres (sample1-8) from four frozen-thawed embryos to multiple displacement amplify. After enzyme digestion, fluorescent labeling, purification and quantify, amplification products hybridized aCGH chips. Hybridized aCGH chips scanned by Agilent Scanner. Obtained images used Feature exaction9.5read and analyze data and get the results.Results:All of8blastomeres were amplified successfully. The mean concentration of the products was883.06±34.63μg/ml.The mean purity was1.75±0.04. The mean yield was17.66±0.69μg. Samples1-4were biopsied from El. The result of sample1detecting by aCGH was47, XX, del(5)(p15.33-p12), del(9)(ql3-q34.13),+21. It was different from samples2-4which were46, XX. E1was mosaicism. Both of sample5and6were biopsied from E2. The result of them were47, XX,+19. E2was trisomy19. Sample7was biopsied from E3. It was a normal embryo:46, XX. Sample8was biopsied from E4. It was a normal embryo:46, XY.Conclusion:1、Multiple displacement amplification could amplified single blastomere. The concentration and purity of the products were stability. It was able to meet the detection of array comparative genomic hybridization.2、aCGH could detect whole genome aneuploidy of blastomeres biopsied from human embryos as preimplantation genetic screening in48hours. aCGH technology could make up for the shortcomings of routine methods. It did not affect fresh embryos’transfer and avoided the damage of cryopreservation and thawing.3、Apart of normal fertilization embryos is of chromosomal abnormality, and quite a number of them are mosaicism. These embryos of Chromosome abnormalities may lead to low implantation rates and high abortion rate after transplantation.