Improvement of Pregnancy Rate in Preimplantation Genetic Diagnosis with FISH Procedure by the Laboratory Optimization and Experiences / 대한불임학회지

OBJECTIVES: This study was performed to evaluate the laboratory system for successful PGD using fluorescence in situ hybridization (FISH) and the clinical outcome of PGD cycles in five years experiences. METHODS: A total of 181 PGD-FISH cycles of 106 couples were performed, and diagnosed chromosome normality in the preimplantation embryos. The laboratory and clinical data were classified by the following optimization steps, and statistically analyzed. Phase I: Blastomere biopsy with two kinds of pipettes, removal of cytoplasmic proteins without treatment of pepsin and culture of biopsied embryos with single medium; Phase II: Blatomere biopsy with single pipette, removal of cytoplasmic proteins with pepsin and culture of biopsied embryos with single medium; Phase III: Blastomere biopsy with single pipette, removal of cytoplasmic proteins with pepsin and culture of biopsied embryos with sequential media. RESULTS: A total of 3,209 oocytes were collected, and 83.8% (2,212/2,640) of fertilization rate was obtained by ICSI procedure. The successful blastomere biopsies were accomplished in 98.6% (2,043/2,071) of embryos, and the successful diagnosis rate of FISH was 94.7% (1,935/ 2,043) of blastomeres from overall data. Embryo transfers with normal embryos were conducted in 93.9% (170/181) of started cycles. There was no difference in the successful rate of biopsy and diagnosis among Phase I, II and III. However, the pregnancy rate per embryo transfer of Phase III (38.8%, 26/67) was significantly (p<0.05) higher than those of Phase I (13.9%, 5/36) and Phase II (14.9%, 10/67). CONCLUSIONS: The laboratory optimization and experience for the PGD with FISH procedure can increase the pregnancy rate to 38.8% in the human IVF-ET program. Our facility of PGD with FISH provides the great possibility to get a normal pregnancy for the concerned couples by chromosomal aberrations.

Successful Preimplantation Genetic Diagnosis for Ornithine Transcarbamylase Deficiency, Junctional Epidermolysis Bullosa and Lactic Acidosis Using Duplex Nested PCR: Delivery of Healthy Baby by Specific Preimplantation Genetic Diagnosis for Ornithine Tran / 대한산부인과학회잡지

OBJECTIVE: Preimplantation genetic diagnosis (PGD) is reserved for couples with a risk of transmitting a serious and incurable disease, and hence avoids the undesirable therapeutic abortion. Herein, we report the result of PGD to carriers at risk of transmitting ornithine transcarbamylase (OTC) deficiency, junctional epidermolysis bullosa (EB) and lactic acidosis (LA) due to defect of pyruvate dehydrogenase alpha1 gene, respectively. METHODS: The ovarian stimulation, oocyte retrieval and ICSI procedure were undergone by conventional protocols. PGD for single gene disorders was carried out after biopsy of one or two blastomeres from the embryos on the third day. We performed the duplex nested PCR of the simultaneous amplification for the causative mutation loci as well as the SRY gene on Y chromosome in case of OTC deficiency and LA. Two different mutation loci of ITGB4 gene in EB case were amplified by the same protocol. The PCR products were analyzed by agarose gel electrophoresis, restriction fragment length polymorphism analysis or direct DNA sequencing. RESULTS: A total of 26 embryos were analyzed by duplex nested PCR. One or two blastomeres were biopsied, and successful diagnosis rate of PGD with PCR was 92.3% (24/26). There was no contamination in all PCR samples of negative controls (n=67). Five embryos (19.2%) were diagnosed as normal embryos, which were transferred to the mothers' uterus in each cases. In OTC deficiency case, singleton pregnancy was established. At 17 weeks of gestation, genetic normality of OTC gene in fetus was confirmed by amniocentesis. A healthy baby was successfully delivered at 36 weeks of gestation in OTC deficiency case. Unfortunately, pregnancies were not achievement in cases of EB and LA. CONCLUSION: This is the first report in Korea that healthy baby was born after specific PGD for OTC deficiency. Our results demonstrate that duplex nested PCR for single cell is an efficient method in identifying the gender and single gene mutation or two different mutation loci, simultaneously. This PGD procedure could provide normal healthy baby to the couple with a high risk of transmitting genetic diseases.

Development of an Efficient Method for Obtaining Metaphase Chromosomes in Individual Blastomeres of Mouse and Human Preimplantaion Embryos: Effect of Microtubule Depolymerizing Agents / 대한불임학회지

OBJECTIVES: The development of an useful method for obtaining metaphase chromosomes from a biopsied blastomere would allow differentiation between embryos with balanced and normal chromosome complements in the preimplantation genetic diagnosis for chromosomal translocations. This study was performed to evaluate the effects of microtubule depolymerizing agents (MTDAs) on the blastomeres of mouse and human preimplantation embryos, and to establish an effective method for obtaining metaphase chromosomes of biopsied blastomeres in human early embryos. MATERIALS AND MEHTODS: Early embryos (2-4 cell stage) from superovulated mice (ICR strain) were collected and treated with single or mixture MTDAs, such as vinblastine, nocodazole and colcemid. After the treatment of MTDAs for 16 hours, the metaphase aquisition (MA) rates were evaluated by the observation of chromosome status with bis-benzimide or DAPI staining. The optimal condition from the above experiment was applied to human embryos, which were developed from abnormal fertilization (3-pronuclei). Fluorescence in-situ hybridization (FISH) with whole chromosome probes was conducted on the human metaphase chromosomes by the MTDAs. RESULTS: In mouse embryos, the effective concentrations of each MTDAs for obtaining metaphase chromosomes were 1.0 micrometer of vinblastine (20.3%), 5.0 micrometer of nocodazole (28.1%) and 1.0 micrometer colcemid (55.6%), respectively. The highest MA rate (91.2%) in the mouse embryos was obtained by a mixture of vinblastine (1.0 micrometer) and nocodazole (1.0 micrometer). In the human embryos, the metaphase chromosomes of blastomeres were obtained in 44 of 113 blastomeres (38.9%) by treatment of the mixture of vinblastine and nocodazole. FISH signals of the metaphase chromosomes were successfully observed in human individual blastomeres. CONCLUSIONS: The treatment of a mixture MTDAs for obtaining metaphase chromosomes was an efficient method, and the MA rate was above 90% in the mouse embryos. However, only a relatively small proportions of the blastomeres yielded metaphase chromosomes by the MTDAs in the human embryos. The inconsistent effects of MTDAs may be related to the variation of different species and the poor developmental potency of abnormally fertilized human embryos. We should develop more reliable and efficient methods for obtaining the metaphase chromosomes in the biopsied blastomeres of human preimplantation embryos.

Development of an Efficient Method for Obtaining Metaphase Chromosomes in Individual Blastomeres of Mouse and Human Preimplantaion Embryos: Effect of Microtubule Depolymerizing Agents / 대한불임학회지

OBJECTIVES: The development of an useful method for obtaining metaphase chromosomes from a biopsied blastomere would allow differentiation between embryos with balanced and normal chromosome complements in the preimplantation genetic diagnosis for chromosomal translocations. This study was performed to evaluate the effects of microtubule depolymerizing agents (MTDAs) on the blastomeres of mouse and human preimplantation embryos, and to establish an effective method for obtaining metaphase chromosomes of biopsied blastomeres in human early embryos. MATERIALS AND MEHTODS: Early embryos (2-4 cell stage) from superovulated mice (ICR strain) were collected and treated with single or mixture MTDAs, such as vinblastine, nocodazole and colcemid. After the treatment of MTDAs for 16 hours, the metaphase aquisition (MA) rates were evaluated by the observation of chromosome status with bis-benzimide or DAPI staining. The optimal condition from the above experiment was applied to human embryos, which were developed from abnormal fertilization (3-pronuclei). Fluorescence in-situ hybridization (FISH) with whole chromosome probes was conducted on the human metaphase chromosomes by the MTDAs. RESULTS: In mouse embryos, the effective concentrations of each MTDAs for obtaining metaphase chromosomes were 1.0 micrometer of vinblastine (20.3%), 5.0 micrometer of nocodazole (28.1%) and 1.0 micrometer colcemid (55.6%), respectively. The highest MA rate (91.2%) in the mouse embryos was obtained by a mixture of vinblastine (1.0 micrometer) and nocodazole (1.0 micrometer). In the human embryos, the metaphase chromosomes of blastomeres were obtained in 44 of 113 blastomeres (38.9%) by treatment of the mixture of vinblastine and nocodazole. FISH signals of the metaphase chromosomes were successfully observed in human individual blastomeres. CONCLUSIONS: The treatment of a mixture MTDAs for obtaining metaphase chromosomes was an efficient method, and the MA rate was above 90% in the mouse embryos. However, only a relatively small proportions of the blastomeres yielded metaphase chromosomes by the MTDAs in the human embryos. The inconsistent effects of MTDAs may be related to the variation of different species and the poor developmental potency of abnormally fertilized human embryos. We should develop more reliable and efficient methods for obtaining the metaphase chromosomes in the biopsied blastomeres of human preimplantation embryos.

Outcome of Preimplantation Genetic Diagnosis for Chromosome Aneuploidy and Genetic Disease / 대한불임학회지

OBJECTIVES: Chromosome aneuploidy is associated with recurrent abortion and congenital anomaly and genetic diseases occur repeatedly in the specific families. Preimplantation genetic diagnosis (PGD) can prevent aneuploidy or genetic disease by selecting normal embryos before implantation and is an alternative to prenatal diagnosis. The aim of this study is to assess the outcome of PGD cycles by using FISH or PCR, and to determine the clinical usefulness and values in patients with risk of chromosomal aneuploidy or genetic disease. MATERIALS AND METHODS: From 1995 to Apr. 2001, a total of 108 PGD cycles in 65 patients with poor reproductive outcome were analyzed. The indications of PGD were translocation (n=49), inversion (n=2), aneuploidy screening (n=7), Duchenne muscular dystrophy (n=5) and spinal muscular atrophy (n=2). PGD was applied due to the history of recurrent abortion, previous birth of affected child or risk of aneuploidy related to sex chromosome aneuploidy or old age. Blastomere biopsy was performed in 6~10 cell stage embryo after IVF with ICSI. In the single blastomere, chromosome aneuploidy was diagnosed by using FISH and PCR was performed for the diagnosis of exon deletion in DMD or SMA. RESULTS: The FISH or PCR amplification was successful in 94.3% of biopsied blastomeres. The rate of transferable balanced embryos was 24.0% in the chromosome translocation and inversion, 57.1% for the DMD and SMA, and 28.8% for the aneuploidy screening. Overall hCG positive rate per transfer was 17.8% (18/101) and clinical pregnancy rate was 13.9% (14/101) (11 term pregnancy, 3 abortion, and 4 biochemical pregnancy). The clinical pregnancy rate of translocation and inversion was 12.9% (11/85) and abortion rate was 27.3% (3/11). In the DMD and SMA, the clinical pregnancy rate was 33.3% (3/9) and all delivered at term. The PGD results were confirmed by amniocentesis and were correct. When the embryos developed to compaction or morula, the pregnancy rate was higher (32%) than that of the cases without compaction (7.2%, p<0.01). CONCLUSIONS: PGD by using FISH or PCR is useful to get normal pregnancy by reducing spontaneous abortion associated with chromosome aneuploidy in the patients with structural chromosome aberration or risk of aneuploidy and can prevent genetic disease prior to implantation.

Outcome of Preimplantation Genetic Diagnosis for Chromosome Aneuploidy and Genetic Disease / 대한불임학회지

OBJECTIVES: Chromosome aneuploidy is associated with recurrent abortion and congenital anomaly and genetic diseases occur repeatedly in the specific families. Preimplantation genetic diagnosis (PGD) can prevent aneuploidy or genetic disease by selecting normal embryos before implantation and is an alternative to prenatal diagnosis. The aim of this study is to assess the outcome of PGD cycles by using FISH or PCR, and to determine the clinical usefulness and values in patients with risk of chromosomal aneuploidy or genetic disease. MATERIALS AND METHODS: From 1995 to Apr. 2001, a total of 108 PGD cycles in 65 patients with poor reproductive outcome were analyzed. The indications of PGD were translocation (n=49), inversion (n=2), aneuploidy screening (n=7), Duchenne muscular dystrophy (n=5) and spinal muscular atrophy (n=2). PGD was applied due to the history of recurrent abortion, previous birth of affected child or risk of aneuploidy related to sex chromosome aneuploidy or old age. Blastomere biopsy was performed in 6~10 cell stage embryo after IVF with ICSI. In the single blastomere, chromosome aneuploidy was diagnosed by using FISH and PCR was performed for the diagnosis of exon deletion in DMD or SMA. RESULTS: The FISH or PCR amplification was successful in 94.3% of biopsied blastomeres. The rate of transferable balanced embryos was 24.0% in the chromosome translocation and inversion, 57.1% for the DMD and SMA, and 28.8% for the aneuploidy screening. Overall hCG positive rate per transfer was 17.8% (18/101) and clinical pregnancy rate was 13.9% (14/101) (11 term pregnancy, 3 abortion, and 4 biochemical pregnancy). The clinical pregnancy rate of translocation and inversion was 12.9% (11/85) and abortion rate was 27.3% (3/11). In the DMD and SMA, the clinical pregnancy rate was 33.3% (3/9) and all delivered at term. The PGD results were confirmed by amniocentesis and were correct. When the embryos developed to compaction or morula, the pregnancy rate was higher (32%) than that of the cases without compaction (7.2%, p<0.01). CONCLUSIONS: PGD by using FISH or PCR is useful to get normal pregnancy by reducing spontaneous abortion associated with chromosome aneuploidy in the patients with structural chromosome aberration or risk of aneuploidy and can prevent genetic disease prior to implantation.