The Application Of FISH In Analysing Aneupoidy Of Preimplanted Embryos

The object of our study is to analyse the incidence of aneuploidy for chromosomes18, X and Y using of fluorescence in situ hybridization (FISH) in blastomeres from preimplanted embryos, detect probe denaturation method and the relationdship between advanced maternal age, severe male factor infertility, numbers of implantation failure, numbers of miscarriage and aneuploidy of preimplanted embryos.Our study is made of two parts. The first part is two kinds of probe denaturation methods on the influence of fluorescence in situ hybridization (FISH) signals. First we collected23embryos from the IVF/ICSI under conventional rules of our center. Embryos which was not suitable for embryo-transfer IVF/ICSI treatment cycles.And we get the information conset. Embryos were biopsied by using1.48um diode laser system, blastomeres were fixed by using HCL/Tween-20+Methanol/glacial acetic acidmethod. Then two kinds of probe denaturation methods (separative-denaturation and co-denaturation) was used to the nucleus determine aneuploidy involving the simultaneous use of chromose-specific deoxyribonucleic acid probes of18, X and Y chromosomes marked with blue, green, red, respectively.95.65%of embryos were biopsied,97.27%of blastomeres were fixed. The hybridazation rates was significantly higher in co-denaturation group than in separative-denaturation group(97.37%vs87.10%, P<0.05). The signal integrity rate was no significant difference between co-denaturation group and separative-denaturation (98.64%vs92.59%, P>0.05). The signal overlap rate was no significant difference between co-denaturation group and separative-denaturation(9.60%vs12.00%, P>0.05).The second part is the application of FISH in analysing aneupoidy of embryos. First we collected76embryos from the IVF/ICSI under conventional rules of our center. Embryos which was not suitable for embryo-transfer IVF/ICSI treatment cycles.And we get the information conset. Embryos were biopsied by using1.48um diode laser system, blastomeres were fixed by using HCL/Tween-20+Methanol/glacial acetic acidmethod. Then co-denaturation was used to the nucleus determine aneuploidy involving the simultaneous use of chromose-specific deoxyribonucleic acid probes of18, X and Y chromosomes marked with blue, green, red, respectively.96.05%of embryos were biopsied,97.51%of blastomeres were fixed,96.42%were hybridazated successfully. Of3chromosomes tested, numeric aberrations can be found including polyploidy, haploidy and mosaicism. The aneuploid rate of the group of female age≥35was significantly higher than female age<35(57.14%vs33.33%, P<0.05). The aneuploid rate had no significant difference between the group of severe male factor infertility and the group of no severe male factor infertility(43.49%vs33.33%, P>0.05). Implantation failure number≥3group and implantation failure number<3group, the aneuploid rate of the former was significantly higher than the latter(66.67%vs38.46%, P<0.05). There is no significant deference of aneuploid rate between miscarriage number≥2group and miscarriage number<2group(55.56%vs36.36%, P<0.05). Thus it can be seen that advanced maternal age, severe male factor infertility, repeated implantation failure and recurrent miscarriage can influence aneuploidy of embryos, and these embryos of chromosome abnormalities may lead to low implantation rates and high abortion rate after transplantation. So these patients are suggested to detect aneuploidy using FISH to screen normal embryos to increase pregnancy rate and live birth rate and reduce abortion rate.