• Clinical and Experimental Reproductive Medicine
• /
• 제38권3호
• /
• pp.126-134
• /
• 2011

Preimplantation genetic diagnosis (PGD) is gradually widely used in prevention of gene diseases and chromosomal abnormalities. Much improvement has been achieved in biopsy technique and molecular diagnosis. Blastocyst biopsy can increase diagnostic accuracy and reduce allele dropout. It is cost-effective and currently plays an important role. Whole genome amplification permits subsequent individual detection of multiple gene loci and screening all 23 pairs of chromosomes. For PGD of chromosomal translocation, fluorescence $in-situ$ hybridization (FISH) is traditionally used, but with technical difficulty. Array comparative genomic hybridization (CGH) can detect translocation and 23 pairs of chromosomes that may replace FISH. Single nucleotide polymorphisms array with haplotyping can further distinguish between normal chromosomes and balanced translocation. PGD may shorten time to conceive and reduce miscarriage for patients with chromosomal translocation. PGD has a potential value for mitochondrial diseases. Preimplantation genetic haplotyping has been applied for unknown mutation sites of single gene disease. Preimplantation genetic screening (PGS) using limited FISH probes in the cleavage-stage embryo did not increase live birth rates for patients with advanced maternal age, unexplained recurrent abortions, and repeated implantation failure. Polar body and blastocyst biopsy may circumvent the problem of mosaicism. PGS using blastocyst biopsy and array CGH is encouraging and merit further studies. Cryopreservation of biopsied blastocysts instead of fresh transfer permits sufficient time for transportation and genetic analysis. Cryopreservation of embryos may avoid ovarian hyperstimulation syndrome and possible suboptimal endometrium.

• 대한생식의학회:학술대회논문집
• /
• 대한불임학회 2003년도 제44차 춘계학술대회
• /
• pp.15-18
• /
• 2003

• Clinical and Experimental Reproductive Medicine
• /
• 제46권1호
• /
• pp.22-29
• /
• 2019

Objective: As paternal age increases, the quality of sperm decreases due to increased DNA fragmentation and aneuploidy. Higher levels of structural chromosomal aberrations in the gametes ultimately decrease both the morphologic quality of embryos and the pregnancy rate. In this study, we investigated whether paternal age affected the euploidy rate. Methods: This study was performed using the medical records of patients who underwent in vitro fertilization (IVF) procedures with preimplantation genetic screening (PGS) from January 2016 to August 2017 at a single center. Based on their morphological grade, embryos were categorized as good- or poor-quality blastocysts. The effects of paternal age were elucidated by adjusting for maternal age. Results: Among the 571 total blastocysts, 219 euploid blastocysts were analyzed by PGS (38.4%). When the study population was divided into four groups according to both maternal and paternal age, significant differences were only noted between groups that differed by maternal age (group 1 vs. 3, p= 0.031; group 2 vs. 4, p= 0.027). Further analysis revealed no significant differences in the euploidy rate among the groups according to the morphological grade of the embryos. Conclusion: Paternal age did not have a significant impact on euploidy rates when PGS was performed. An additional study with a larger sample size is needed to clarify the effects of advanced paternal age on IVF outcomes.

• 대한유전성대사질환학회지
• /
• 제5권1호
• /
• pp.108-115
• /
• 2005

Inherited metabolic diseases (IMD) comprise a large class of genetic diseases involving disorders of metabolism. The majorities are due to defects of single genes that code for enzymes that facilitate conversion of various substances into others. Because of the multiplicity of conditions, many different diagnostic tests are used for screening of IMD. Molecular genetic diagnosis is the detection of pathogenic mutations in DNA and/or RNA samples and is becoming a much more common practice in medicine today. The purpose of molecular genetic testing in IMD includes diagnostic testing, pre-symptomatic testing, carrier screening, prenatal diagnosis, preimplantation testing, and population screening. However, because of the complexity, difficulty in interpreting the result, and the ethical considerations, an understanding of technical, conceptual, and practical aspects of molecular genetic diagnosis is mandatory.

• 한국발생생물학회:학술대회논문집
• /
• 한국발생생물학회 1998년도 제4차 학술발표대회 및 정기총회
• /
• pp.12-18
• /
• 1998

Tremendous progress has been made over the past quarter-century studying the genetics of gametogenesis and the resulting gametes and embryos. Studies merging molecular techniques and conventional cytogenetics are now beginning to bridge the gap between what we have learned about the meiotic process in males and females and what we know of the mitotic chromosomes of zygotes. Numerical abnormalities in sperm, oocytes and embryo can now diagnosed by fluorescence in situ hybridization (FISH). "At risk" couples can, therefore, have only unaffected embryos replaced in the sterus and avoid the possibility of terminating a pregnancy that might only be diagnosed as affected later gestation. Single-cell genetic analysis has also provided powerful tools for studying genetic defects arising during early human development. Recent studies of sperms, oocytes and cleavage-stage human embryos have revealed an unexpectedly high incidence. These genetic abnormalities are likely to contribute to early pregnancy loss and have important implications for improving pregnancy rates in infertile couples by assisted reproduction. The widespread use of preimplantation genetic diagnosis (PGD) awaits further documentatio of safety and accuracy. Other issues also must be addressed. First, the ethical issues regarding germ cell and embryo screening must be addressed including what diseases are serious enough to warrant the procedure. Another concern is the use of this technology for non-genetic disorders such as gender selection. Finally, the experimental nature of these procedure must continually be discussed with patients, and long-term follow-up studies must be undertaken. Development of more accurate and less expensive assays coupled with improved assisted reproductive technology success rates may make PGD a more widely use clinical tool. The future awaits these development.velopment.

• Clinical and Experimental Reproductive Medicine
• /
• 제41권4호
• /
• pp.168-173
• /
• 2014

The purpose of this study is to report a successful twin pregnancy and delivery in a female patient with X-linked dominant incontinentia pigmenti (IP) who underwent assisted reproductive technology followed by preimplantation genetic screening (PGS). A 29-year-old female with IP had a previous history of recurrent spontaneous abortion. A molecular analysis revealed the patient had a de novo mutation, 1308_1309insCCCCTTG(p.Ala438ProfsTer26), in the inhibitor of the kappa B kinase gamma gene located in the Xq28 region. IVF/ICSI and PGS was performed, in which male embryos were sexed using array-based comparative genomic hybridization (aCGH). After IVF/ICSI and PGS using aCGH on seven embryos, two euploid male blastocysts were transferred with a 50% probability of a viable male pregnancy. The dizygotic twin pregnancy was confirmed and the amniocentesis results of each twin were normal with regard to the mutation found in the mother. The patient delivered healthy twin babies during the 37th week of gestation. This case shows the beneficial role of PGS in achieving a successful pregnancy through euploid male embryo gender selection in a woman with X-linked dominant IP with a history of multiple male miscarriages.

• Clinical and Experimental Reproductive Medicine
• /
• 제51권1호
• /
• pp.85-90
• /
• 2024

Objective: The purpose of this study was to compare fresh and frozen-thawed euploid blastocyst transfer protocols following preimplantation genetic screening (PGS) in cases of advanced maternal age. Methods: A total of 330 patients were examined retrospectively. PGS was performed on the embryos of 146 patients for whom fresh transfers were chosen. In contrast, frozen-thawed euploid single embryo transfer (ET) was selected after PGS for 184 patients, and their embryos were vitrified. The percentage of euploid embryos and rates of implantation, pregnancy, and pregnancy continuity, as well as clinical and biochemical abortion rates, were compared. Results: The numbers of retrieved oocytes, metaphase II oocytes, and fertilized ova were greater in the frozen-thawed group. The percentages of euploid embryos were comparable between the fresh and frozen-thawed groups (32% vs. 34.8%, respectively). The rates of implantation (46.6%vs. 62.5%), pregnancy (50% vs. 66.8%), ongoing pregnancy (38.4% vs. 53.8%), and live birth percentage (37.0% vs. 53.8%) were significantly higher in the frozen-thawed group. However, no significant differences were found in the clinical and biochemical abortion rates. Conclusion: The use of frozen-thawed single euploid ET is associated with increased implantation and pregnancy rates compared to fresh single euploid ET with PGS.

• Journal of Genetic Medicine
• /
• 제7권2호
• /
• pp.125-132
• /
• 2010

목 적: 착상전 유전진단(preimplantation genetic diagnosis, PGD)은 유전질환을 가진 부부들을 대상으로 체외수정을 통해 획득한 배아에서 유전진단을 하는 방법이다. 다양한 유전질환을 가진 부부에게 그 질환에 맞는 PGD의 설계가 진행되어야 하기 때문에 PGD 시행 전유전상담을 시행하는 것은 PGD 설계에 있어서 매우 중요하다. 이에, PGD 시행 시 필요한 유전상담의 내용에 대해 환자 및 가족과 전문가의 구체적인 의견을 수렴하고 분석하고자 하였다. 대상 및 방법: 본 연구는 PGD에 있어서 유전상담의 필요성과 중요성에 대한 의견을 알아보고자, 2010년 2월 3일부터 4월 30일까지 PGD를 실시 또는 실시 예정인 부부들과 PGD 관련 전문가들을 대상으로 이메일과 직접 설문지를 배포하여 설문조사를 실시하였다. 결 과: 환자 60명과 전문가 31명을 포함하여 총 91명이 설문조사에 응답하였으며, 환자들은 염색체 이상 질환 49명(81.7%)과 단일유전자 이상 질환 11명(18.3%) 이었다. 설문에 응답한 환자와 전문가 모두 유전상담이 PGD의 의료서비스 일환으로 반드시 필요하다고 답하였다. 환자의 충분한 이해를 위하여 필요한 유전상담의 시간에 대해 환자와 가족 그리고 전문가 의견을 수렴한 결과, 각각 45명(75.0%)과 23명(74.2%)이 적정한 유전상담시간을 30분 이상이라고 응답하였다. 하지만, 현 의료시스템에서는 짧은 진료시간 내 진료와 유전상담을 동시에 진행함으로써 환자에게 완벽한 정보제공이 이루어지지 않는 것으로 나타났다. 한편, 전문가 그룹에서는 진료시간의 부족과 유전질환의 정보 부족이 유전상담의 어려운 점이라고 답하였으며, 이에 비 의사(non-MD) 전문유전상담사가 필요하다는 의견이 30명(96.7%)으로 높게 나타났다. 환자와 가족들은 PGD 시술 시 예기치 못한 결과의 가능성, 환자가 가진 유전질환의 위험을 예방할 수 있는 선택사항, 환자가 가지고 있는 유전질환의 위험도 평가, 유전자 검사 시 검사의 목적 설명 및 검사기술의 한계점과 오진률의 설명, PGD 시술 전반에 관한 기술적인 정보 등에 대하여 관심을 가지고 있으며 더 자세한 설명을 필요로 하는 것으로 나타났다. 이에 대한 전문가 의견 역시 환자 및 가족이 관심 있고 자세한 설명을 원하는 정보와 대부분 일치하였다. 이에 따라 환자의 요구와 의견으로 나타난 위의 결과들을 향후 PGD를 위한 유전상담의 지침(guide-line) 구축 시 반영하여야 할 것으로 사료된다. 결 론: 본 연구에서 유전진단과 생식의학 기술의 발전과 더불어 PGD의 적용과 효율성 등에 대한인식이 높아짐에 따라, PGD를 시행함에 있어서 구체적이고 체계적인 유전상담이 필요하다는 것을 확인할 수 있었다. 본 연구의 설문조사 결과가 향후 PGD를 위한 유전상담 지침서(guideline)에 반영되어 적절한 PGD의 설계, 실시, 사후관리에 큰 도움이 되기를 기대한다.

• Clinical and Experimental Reproductive Medicine
• /
• 제44권1호
• /
• pp.40-46
• /
• 2017

Objective: To describe in vitro development of human embryos derived from an individual with a homozygous pathogenic variant in NLRP7 (19q13.42) and recurrent hydatidiform mole (HM), an autosomal recessive condition thought to occur secondary to an oocyte defect. Methods: A patient with five consecutive HM pregnancies was genomically evaluated via next generation sequencing followed by controlled ovarian hyperstimulation, in vitro fertilization (IVF) with intracytoplasmic sperm injection, embryo culture, and preimplantation genetic screening. Findings in NLRP7 were recorded and embryo culture and biopsy data were tabulated as a function of parental origin for any identified ploidy error. Results: The patient was found to have a pathogenic variant in NLRP7 (c.2810+2T>G) in a homozygous state. Fifteen oocytes were retrieved and 10 embryos were available after fertilization via intracytoplasmic sperm injection. Developmental arrest was noted for all 10 embryos after 144 hours in culture, thus no transfer was possible. These non-viable embryos were evaluated by karyomapping and all were diploid biparental; two were euploid and eight had various aneuploidies all of maternal origin. Conclusion: This is the first report of early human embryo development from a patient with any NLRP7 mutation. The pathogenic variant identified here resulted in global developmental arrest at or before blastocyst stage. Standard IVF should therefore be discouraged for such patients, who instead need to consider oocyte (or embryo) donation with IVF as preferred clinical methods to treat infertility.

• Clinical and Experimental Reproductive Medicine
• /
• 제29권4호
• /
• pp.269-278
• /
• 2002

Objective s: 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$\sim$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 emb ryos 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 n ormal 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.