Objective: To evaluate the effect of preimplantation genetic diagnosis (PGD) conducted for women who had Down syndrome pregnancy previously. Methods: Trisomy 21 was diagnosed by using fluorescence in site hybridizatio...Objective: To evaluate the effect of preimplantation genetic diagnosis (PGD) conducted for women who had Down syndrome pregnancy previously. Methods: Trisomy 21 was diagnosed by using fluorescence in site hybridization (FISH) before embryo transfer in two women who had Down syndrome pregnancies. Each received one or two PGD cycles respectively. Results: Case 1: one PGD cycle was conducted, two oocytes were fertilized and biopsied. One embryo is of trisomy 21 and the other of monosomy 21. No embryo was transferred. Case 2: two PGD cycles were conducted, in total, sixteen oocytes were fertilized and biopsied. Four embryos were tested to be normal, six of trisomy 21, and one of monosomy 21. Five had no signal. Four normal embryos were transferred but no pregnancy resulted. Conclusion: For couples who had pregnancies with Down syndrome pre-viously, PGD can be considered, and has been shown to be an effective strategy.展开更多
In order to establish a simple and useful way for preimplantation genetic diagnosis (PGD) of chromosomal diseases in general IVF laboratory, the methods that are most commonly used in the embryo biopsy, fixation of bl...In order to establish a simple and useful way for preimplantation genetic diagnosis (PGD) of chromosomal diseases in general IVF laboratory, the methods that are most commonly used in the embryo biopsy, fixation of blastomere and fluorescence in situ hybridization were compared. The three aspects of PGD were analyzed respectively. There was no significant difference in further de- velopment capacity of embryos between mechanical (79.7%) and chemical biopsy group (78.6%) (P>0.05). In this study, more cells were successfully fixed with the Tween/HCL method (93.8%) than with the methanol/acetic acid method (80.5%, P<0.05). There was no significant difference in cyto- plasm remains between methanol/acetic acid method and Tween/HCL method (P>0.05). The hy- bridization efficiency of fluorescence in situ hybridization was 89.5% in successive denaturation method and 90.9% in codenaturation method with the difference being not significant (P>0.05). In conclusion, the mechanical or chemical method, Tween/HCL fixation method and codenaturation fluorescence in situ hybridization method can constitute a simple and useful way for PGD of chro- mosomal diseases.展开更多
Preimplantation genetic testing refers to the procedure to determine the genetic status of embryos formed by in vitro fertilization(IVF) prior to initiating a pregnancy.Traditional genetic methods for preimplantation ...Preimplantation genetic testing refers to the procedure to determine the genetic status of embryos formed by in vitro fertilization(IVF) prior to initiating a pregnancy.Traditional genetic methods for preimplantation genetic diagnosis(PGD) examine distinct parts of an individua genome, require the development of a custom assay for every patient family, and are time consuming and inefficient. In the last decade technologies for wholegenome amplification(WGA) from single cells have led to innovative strategies for preimplantation testing.Applications of WGA technology can lead to a universa approach that uses single-nucleotide polymorphisms(SNPs) and mutations across the entire genome for the analysis. Single-cell WGA by multiple displacement amplification has enabled a linkage approach to PGD known as "preimplantation genetic haplotyping", as well as microarray-based techniques for preimplantation diagnosis. The use of microarrays in preimplantation diagnosis has provided genome-wide testing for gains or losses of single chromosomes(aneuploidies)or chromosomal segments. Properly designed randomized controlled trials are, however, needed to determine whether these new technologies improve IVF outcomes by increasing implantation rates and decreasing mis-carriage rates. In genotype analysis of single cells, allele dropout occurs frequently at heterozygous loci. Preimplantation testing of multiple cells biopsied from blastocysts, however, can reduce allele dropout rates and increase the accuracy of genotyping, but it allows less time for PGD. Future development of fast SNP microarrays will enable a universal preimplantation testing for aneuploidies, single-gene disorders and unbalanced translocations within the time frame of an IVF cycle.展开更多
Preimplantation genetic diagnosis allows to test the genetic status of embryos prior to implantation. In order to obtain genetic material, on which carry out a genetic diagnosis, a procedure named embryo biopsy is req...Preimplantation genetic diagnosis allows to test the genetic status of embryos prior to implantation. In order to obtain genetic material, on which carry out a genetic diagnosis, a procedure named embryo biopsy is required. In the last two decades, embryo biopsy at the cleavage stage has been the mostly performed procedure. However, recently, alternative methods allowing the retrieval of a larger number of cells (blastocyst stage biopsy), or representing a valid alternative to overcome ethical issues (polar body biopsy) have obtained increasing consensus. This article reviews different methods of embryo biopsy and points out their positive and negative aspects.展开更多
Preimplantation genetic diagnosis (PGD), as a new assisted reproductive technology which can select normal embryos for transplantation combined with in-vitro fertilization and embryo transfer(IVF-ET)through the analys...Preimplantation genetic diagnosis (PGD), as a new assisted reproductive technology which can select normal embryos for transplantation combined with in-vitro fertilization and embryo transfer(IVF-ET)through the analysis of genetic materials before embryo implantation, holds a more and more important position in the diagnosis of genetic diseases and has made an important significance to the Aristogenics.PGD is an important aspect of assisted reproduction technology(ART)with its rapid development. Continuous appearances and comprehensive applications of new methods and technologies have greatly developed the PGD. In this review, we introduce some new methods and their principles about the new research advances of PGD.展开更多
Atelosteogenesis type II (AO2) and diastrophic dysplasia (DTD) are two recessively inherited, severe skeletal dysplasias caused by mutations in the SLC26A2 gene. AO2 is an invariably lethal condition, while DTD patien...Atelosteogenesis type II (AO2) and diastrophic dysplasia (DTD) are two recessively inherited, severe skeletal dysplasias caused by mutations in the SLC26A2 gene. AO2 is an invariably lethal condition, while DTD patients may reach adult life, although both diseases have overlapping diagnostic features. Here we report a patient with an intermediate phenotype between AO2 and DTD and present the successful application of preimplantation genetic diagnosis (PGD) in this situation. Sequencing of SLC26A2 alleles in the infant identified two compound heterozygous mutations, p.Arg178Ter and p.Arg279Trp, of paternal and maternal origin, respectively. At request from the parents, PGD was developed by haplotype mapping of parental SLC26A2 alleles in eleven five-day embryos. Transference to the mother was attempted twice, finally resulting in pregnancy and delivery of a healthy baby. This exemplifies the utility of PGD for inherited lethal conditions with a significant risk of recurrence, and highlights the importance of accurate diagnosis of skeletal dysplasias with prenatal manifestation.展开更多
Objective: Embryonic chromosomal abnormality is one of the main reasons for in vitro fertilization (IVF) failure. This study aimed at evaluating the value of Fluorescence in-situ Hybridization (FISH)-based Preimplanta...Objective: Embryonic chromosomal abnormality is one of the main reasons for in vitro fertilization (IVF) failure. This study aimed at evaluating the value of Fluorescence in-situ Hybridization (FISH)-based Preimplantation Genetic Diagnosis (PGD) in screening for embryonic chromosomal abnormality to increase the successful rate of IVF. Method: Ten couples, four with high risk of chromosomal abnormality and six infertile couples, underwent FISH-based PGD during IVF procedure. At day 3, one or two blastomeres were aspirated from each embryo. Biopsied blastomeres were examined using FISH analysis to screen out embryos with chromosomal abnormalities. At day 4, embryos without detectable chromosomal abnormality were transferred to the mother bodies as in regular IVF. Results: Among 54 embryos screened using FISH-based PGD, 30 embryos were detected to have chromosomal abnormalities. The 24 healthy embryos were implanted, resulting in four clinical pregnancies, two of which led to successful normal birth of two healthy babies; one to ongoing pregnancy during the writing of this article; and one to ectopic pregnancy. Conclusion: FISH-based PGD is an effective method for detecting embryonic chromosomal abnormality, which is one of the common causes of spontaneous miscarriages and chromosomally unbalanced offsprings.展开更多
Conventional PCR methods combined with linkage analysis based on short tandem repeats (STRs) or Karyomapping with single nucleotide polymorphism (SNP) arrays, have been applied to preimplantation genetic diagnosis...Conventional PCR methods combined with linkage analysis based on short tandem repeats (STRs) or Karyomapping with single nucleotide polymorphism (SNP) arrays, have been applied to preimplantation genetic diagnosis (PGD) for spinal muscular atrophy (SMA), an autosome recessive disorder. However, it has limitations in SMA diagnosis by Karyomapping, and these methods are unable to distinguish wild- type embryos with carriers effectively. Mutated allele revealed by sequencing with aneuploidy and linkage analyses (MARSALA) is a new method allowing embryo selection by a one-step next-generation sequencing (NGS) procedure, which has been applied in PGD for both autosome dominant and X-linked diseases in our group previously. In this study, we carried out PGD based on MARSALA for two carrier families with SMA affected children. As a result, one of the couples has given birth to a healthy baby free of mutations in SMA-causing gene. It is the first time that MARSALA was applied to PGD for SMA, and we can distinguish the embryos with heterozygous deletion (carriers) from the wild-type (normal) ones accurately through this NGS-based method. In addition, direct mutation detection allows us to identify the affected embryos (homozygous deletion), which can be regarded as probands for linkage analysis, in case that the affected family member is absent, In the future, the NGS-based MARSALA method is expected to be used in PGD for all monogenetic disorders with known pathogenic gene mutation.展开更多
Preimplantation genetic diagnosis(PGD)gives couples who have a high risk of transmitting genetic disorders to their baby the chance to have a healthy offspring through embryo genetic analysis and selection.Preimplanta...Preimplantation genetic diagnosis(PGD)gives couples who have a high risk of transmitting genetic disorders to their baby the chance to have a healthy offspring through embryo genetic analysis and selection.Preimplantation genetic screening(PGS)is an effective method to select euploid embryos that may prevent repeated implantation failure or miscarriage.However,how and to whom PGS should be provided is a controversial topic.The first successful case of PGD of a human being was reported in 1990,and there have been tremendous improvements in this technology since then.Both embryo biopsy and genetic technologies have been improved dramatically,which increase the accuracy and expand the indications of PGD/PGS.展开更多
Preimplantation genetic diagnosis (PGD) refers to a procedure for genetically analyzing embryos prior to implantation,improving the chance of conception for patients at high risk of transmitting specific inherited dis...Preimplantation genetic diagnosis (PGD) refers to a procedure for genetically analyzing embryos prior to implantation,improving the chance of conception for patients at high risk of transmitting specific inherited disorders.This method has been widely used for a large number of genetic disorders since the first successful application in the early 1990s.Polymerase chain reaction (PCR) and fluorescent in situ hybridization (FISH) are the two main methods in PGD,but there are some inevitable shortcomings limiting the scope of genetic diagnosis.Fortunately,different whole genome amplification (WGA) techniques have been developed to overcome these problems.Sufficient DNA can be amplified and multiple tasks which need abundant DNA can be performed.Moreover,WGA products can be analyzed as a template for multi-loci and multi-gene during the subsequent DNA analysis.In this review,we will focus on the currently available WGA techniques and their applications,as well as the new technical trends from WGA products.展开更多
Charcot-Marie-Tooth (CMT) disease is the most common hereditary neuropathy, with a population prevalence of 1 in 2500. CMT disease type 1A (CMT1A), accounting for ~70% of CMT1 cases and ~ 50% of all CMT cases, is ...Charcot-Marie-Tooth (CMT) disease is the most common hereditary neuropathy, with a population prevalence of 1 in 2500. CMT disease type 1A (CMT1A), accounting for ~70% of CMT1 cases and ~ 50% of all CMT cases, is transmitted in an autosomal dominant manner. CMT1A maps to chromo- some 17pl 1.2 and is caused, in the majority of cases, by a 1.4- Mb tandem duplication that includes the peripheral myelin protein22 (PMP22) gene (Li et al., 2013). The disease usually presents in the first 20 years of age, causing difficulty in walking or running, distal symmetrical muscle weakness and wasting, and sensory loss (van Paassen et al., 2014).展开更多
It is well known that to achieve an acceptable engraftment and survival in stem cell therapy, an human leukocyte antigens(HLA) identical stem cell transplant is strongly required. However, the availability of the HLA ...It is well known that to achieve an acceptable engraftment and survival in stem cell therapy, an human leukocyte antigens(HLA) identical stem cell transplant is strongly required. However, the availability of the HLA matched donors even among family members is extremely limited, so preimplantation HLA typing provides an attractive practical tool of stem cell therapy for children requiring HLA matched stem cell transplantation. The present experience of preimplantation genetic diagnosis(PGD) for HLA typing of over one thousand cases shows that PGD provides the at-risk couples with the option to establish an unaffected pregnancy, which may benefit the affected member of the family with hemoglobinopathies, immunodeficiencies and other congenital or acquired bone marrow failures. Despite ethical issues involved in preimplantation HLA typing, the data presented below show an extremely high attractiveness of this option for the couples with affected children requiring HLA compatible stem cell transplantation.展开更多
Preimplantation genetic diagnosis(PGD)uses molecular biological techniques to genetically diagnose embryos beforein vitro fertilization.The information obtained through PGD can help clinicians select healthy embryos f...Preimplantation genetic diagnosis(PGD)uses molecular biological techniques to genetically diagnose embryos beforein vitro fertilization.The information obtained through PGD can help clinicians select healthy embryos for implantation,prevent the transmission of inherited diseases and help affected families have healthy children.This paper reviews the development of PGD technology,the history of its application to hereditary hearing loss,and the general process of how PGD is applied to screen for hereditary hearing loss.The aim of this review is to demonstrate the reliability of PGD in the primary prevention of hereditary hearing loss,assist clinicians in counseling patients at risk of transmitting an inherited disease,and explore the journey from PGD toin vitro fertilization.Given that the application of PGD technology to hereditary hearing loss varies in different countries and regions,there is still a long way to go before PGD is routinely applied for the primary prevention of hereditary hearing loss.展开更多
基金Project supported by the National Basic Research Program of China(Nos. 2006CB944006 and 2006CB504004)the Key Research Pro-gram of Zhejiang Province, China (No. 2006C13078)the Bureau of Science and Technology of Hangzhou, China (No. 20061123B03)
文摘Objective: To evaluate the effect of preimplantation genetic diagnosis (PGD) conducted for women who had Down syndrome pregnancy previously. Methods: Trisomy 21 was diagnosed by using fluorescence in site hybridization (FISH) before embryo transfer in two women who had Down syndrome pregnancies. Each received one or two PGD cycles respectively. Results: Case 1: one PGD cycle was conducted, two oocytes were fertilized and biopsied. One embryo is of trisomy 21 and the other of monosomy 21. No embryo was transferred. Case 2: two PGD cycles were conducted, in total, sixteen oocytes were fertilized and biopsied. Four embryos were tested to be normal, six of trisomy 21, and one of monosomy 21. Five had no signal. Four normal embryos were transferred but no pregnancy resulted. Conclusion: For couples who had pregnancies with Down syndrome pre-viously, PGD can be considered, and has been shown to be an effective strategy.
文摘In order to establish a simple and useful way for preimplantation genetic diagnosis (PGD) of chromosomal diseases in general IVF laboratory, the methods that are most commonly used in the embryo biopsy, fixation of blastomere and fluorescence in situ hybridization were compared. The three aspects of PGD were analyzed respectively. There was no significant difference in further de- velopment capacity of embryos between mechanical (79.7%) and chemical biopsy group (78.6%) (P>0.05). In this study, more cells were successfully fixed with the Tween/HCL method (93.8%) than with the methanol/acetic acid method (80.5%, P<0.05). There was no significant difference in cyto- plasm remains between methanol/acetic acid method and Tween/HCL method (P>0.05). The hy- bridization efficiency of fluorescence in situ hybridization was 89.5% in successive denaturation method and 90.9% in codenaturation method with the difference being not significant (P>0.05). In conclusion, the mechanical or chemical method, Tween/HCL fixation method and codenaturation fluorescence in situ hybridization method can constitute a simple and useful way for PGD of chro- mosomal diseases.
基金Supported by Department of Pediatrics,Medical College of Wisconsin,Milwaukee,WI,United States
文摘Preimplantation genetic testing refers to the procedure to determine the genetic status of embryos formed by in vitro fertilization(IVF) prior to initiating a pregnancy.Traditional genetic methods for preimplantation genetic diagnosis(PGD) examine distinct parts of an individua genome, require the development of a custom assay for every patient family, and are time consuming and inefficient. In the last decade technologies for wholegenome amplification(WGA) from single cells have led to innovative strategies for preimplantation testing.Applications of WGA technology can lead to a universa approach that uses single-nucleotide polymorphisms(SNPs) and mutations across the entire genome for the analysis. Single-cell WGA by multiple displacement amplification has enabled a linkage approach to PGD known as "preimplantation genetic haplotyping", as well as microarray-based techniques for preimplantation diagnosis. The use of microarrays in preimplantation diagnosis has provided genome-wide testing for gains or losses of single chromosomes(aneuploidies)or chromosomal segments. Properly designed randomized controlled trials are, however, needed to determine whether these new technologies improve IVF outcomes by increasing implantation rates and decreasing mis-carriage rates. In genotype analysis of single cells, allele dropout occurs frequently at heterozygous loci. Preimplantation testing of multiple cells biopsied from blastocysts, however, can reduce allele dropout rates and increase the accuracy of genotyping, but it allows less time for PGD. Future development of fast SNP microarrays will enable a universal preimplantation testing for aneuploidies, single-gene disorders and unbalanced translocations within the time frame of an IVF cycle.
文摘Preimplantation genetic diagnosis allows to test the genetic status of embryos prior to implantation. In order to obtain genetic material, on which carry out a genetic diagnosis, a procedure named embryo biopsy is required. In the last two decades, embryo biopsy at the cleavage stage has been the mostly performed procedure. However, recently, alternative methods allowing the retrieval of a larger number of cells (blastocyst stage biopsy), or representing a valid alternative to overcome ethical issues (polar body biopsy) have obtained increasing consensus. This article reviews different methods of embryo biopsy and points out their positive and negative aspects.
基金National Natural Science Foundation of China ( 30772069)
文摘Preimplantation genetic diagnosis (PGD), as a new assisted reproductive technology which can select normal embryos for transplantation combined with in-vitro fertilization and embryo transfer(IVF-ET)through the analysis of genetic materials before embryo implantation, holds a more and more important position in the diagnosis of genetic diseases and has made an important significance to the Aristogenics.PGD is an important aspect of assisted reproduction technology(ART)with its rapid development. Continuous appearances and comprehensive applications of new methods and technologies have greatly developed the PGD. In this review, we introduce some new methods and their principles about the new research advances of PGD.
基金The authors would like to thank the subjects reported here and Hospital de Clínicas de Porto Alegre Research Fund 12-0467 for supporting this publication.
文摘Atelosteogenesis type II (AO2) and diastrophic dysplasia (DTD) are two recessively inherited, severe skeletal dysplasias caused by mutations in the SLC26A2 gene. AO2 is an invariably lethal condition, while DTD patients may reach adult life, although both diseases have overlapping diagnostic features. Here we report a patient with an intermediate phenotype between AO2 and DTD and present the successful application of preimplantation genetic diagnosis (PGD) in this situation. Sequencing of SLC26A2 alleles in the infant identified two compound heterozygous mutations, p.Arg178Ter and p.Arg279Trp, of paternal and maternal origin, respectively. At request from the parents, PGD was developed by haplotype mapping of parental SLC26A2 alleles in eleven five-day embryos. Transference to the mother was attempted twice, finally resulting in pregnancy and delivery of a healthy baby. This exemplifies the utility of PGD for inherited lethal conditions with a significant risk of recurrence, and highlights the importance of accurate diagnosis of skeletal dysplasias with prenatal manifestation.
文摘Objective: Embryonic chromosomal abnormality is one of the main reasons for in vitro fertilization (IVF) failure. This study aimed at evaluating the value of Fluorescence in-situ Hybridization (FISH)-based Preimplantation Genetic Diagnosis (PGD) in screening for embryonic chromosomal abnormality to increase the successful rate of IVF. Method: Ten couples, four with high risk of chromosomal abnormality and six infertile couples, underwent FISH-based PGD during IVF procedure. At day 3, one or two blastomeres were aspirated from each embryo. Biopsied blastomeres were examined using FISH analysis to screen out embryos with chromosomal abnormalities. At day 4, embryos without detectable chromosomal abnormality were transferred to the mother bodies as in regular IVF. Results: Among 54 embryos screened using FISH-based PGD, 30 embryos were detected to have chromosomal abnormalities. The 24 healthy embryos were implanted, resulting in four clinical pregnancies, two of which led to successful normal birth of two healthy babies; one to ongoing pregnancy during the writing of this article; and one to ectopic pregnancy. Conclusion: FISH-based PGD is an effective method for detecting embryonic chromosomal abnormality, which is one of the common causes of spontaneous miscarriages and chromosomally unbalanced offsprings.
基金supported by the National Natural Science Foundation of China (Nos. 31522034, 31571544 and 31230047)the National High Technology Research and Development Program (No. 2015AA020407)+1 种基金Beijing Municipal Science and Technology Commission (No. D151100002415004)Research Fund of National Health and Family Planning Commission of China (No. 201402004)
文摘Conventional PCR methods combined with linkage analysis based on short tandem repeats (STRs) or Karyomapping with single nucleotide polymorphism (SNP) arrays, have been applied to preimplantation genetic diagnosis (PGD) for spinal muscular atrophy (SMA), an autosome recessive disorder. However, it has limitations in SMA diagnosis by Karyomapping, and these methods are unable to distinguish wild- type embryos with carriers effectively. Mutated allele revealed by sequencing with aneuploidy and linkage analyses (MARSALA) is a new method allowing embryo selection by a one-step next-generation sequencing (NGS) procedure, which has been applied in PGD for both autosome dominant and X-linked diseases in our group previously. In this study, we carried out PGD based on MARSALA for two carrier families with SMA affected children. As a result, one of the couples has given birth to a healthy baby free of mutations in SMA-causing gene. It is the first time that MARSALA was applied to PGD for SMA, and we can distinguish the embryos with heterozygous deletion (carriers) from the wild-type (normal) ones accurately through this NGS-based method. In addition, direct mutation detection allows us to identify the affected embryos (homozygous deletion), which can be regarded as probands for linkage analysis, in case that the affected family member is absent, In the future, the NGS-based MARSALA method is expected to be used in PGD for all monogenetic disorders with known pathogenic gene mutation.
基金supported by the Beijing Municipal Science and Technology Commission (Z131100005213006)the National Natural Science Foundation of China (31230047)the National Basic Research Program of China (2011CB944504)
文摘Preimplantation genetic diagnosis(PGD)gives couples who have a high risk of transmitting genetic disorders to their baby the chance to have a healthy offspring through embryo genetic analysis and selection.Preimplantation genetic screening(PGS)is an effective method to select euploid embryos that may prevent repeated implantation failure or miscarriage.However,how and to whom PGS should be provided is a controversial topic.The first successful case of PGD of a human being was reported in 1990,and there have been tremendous improvements in this technology since then.Both embryo biopsy and genetic technologies have been improved dramatically,which increase the accuracy and expand the indications of PGD/PGS.
基金Project supported by the National Basic Research Program (973) of China (No.2007CB948104)the Natural Science Foundation of Zhejiang Province,China (No.Z207021)
文摘Preimplantation genetic diagnosis (PGD) refers to a procedure for genetically analyzing embryos prior to implantation,improving the chance of conception for patients at high risk of transmitting specific inherited disorders.This method has been widely used for a large number of genetic disorders since the first successful application in the early 1990s.Polymerase chain reaction (PCR) and fluorescent in situ hybridization (FISH) are the two main methods in PGD,but there are some inevitable shortcomings limiting the scope of genetic diagnosis.Fortunately,different whole genome amplification (WGA) techniques have been developed to overcome these problems.Sufficient DNA can be amplified and multiple tasks which need abundant DNA can be performed.Moreover,WGA products can be analyzed as a template for multi-loci and multi-gene during the subsequent DNA analysis.In this review,we will focus on the currently available WGA techniques and their applications,as well as the new technical trends from WGA products.
文摘Charcot-Marie-Tooth (CMT) disease is the most common hereditary neuropathy, with a population prevalence of 1 in 2500. CMT disease type 1A (CMT1A), accounting for ~70% of CMT1 cases and ~ 50% of all CMT cases, is transmitted in an autosomal dominant manner. CMT1A maps to chromo- some 17pl 1.2 and is caused, in the majority of cases, by a 1.4- Mb tandem duplication that includes the peripheral myelin protein22 (PMP22) gene (Li et al., 2013). The disease usually presents in the first 20 years of age, causing difficulty in walking or running, distal symmetrical muscle weakness and wasting, and sensory loss (van Paassen et al., 2014).
文摘It is well known that to achieve an acceptable engraftment and survival in stem cell therapy, an human leukocyte antigens(HLA) identical stem cell transplant is strongly required. However, the availability of the HLA matched donors even among family members is extremely limited, so preimplantation HLA typing provides an attractive practical tool of stem cell therapy for children requiring HLA matched stem cell transplantation. The present experience of preimplantation genetic diagnosis(PGD) for HLA typing of over one thousand cases shows that PGD provides the at-risk couples with the option to establish an unaffected pregnancy, which may benefit the affected member of the family with hemoglobinopathies, immunodeficiencies and other congenital or acquired bone marrow failures. Despite ethical issues involved in preimplantation HLA typing, the data presented below show an extremely high attractiveness of this option for the couples with affected children requiring HLA compatible stem cell transplantation.
基金supported by the grants of the National Natural Science Foundation of China(Major Project No.81830028,Youths Program Nos.81900951 and 81900950)Beijing Municipal Natural Science Foundation Youth Projects(No.7204312)National Key Research and Development Project(No.2020YFC2005201)。
文摘Preimplantation genetic diagnosis(PGD)uses molecular biological techniques to genetically diagnose embryos beforein vitro fertilization.The information obtained through PGD can help clinicians select healthy embryos for implantation,prevent the transmission of inherited diseases and help affected families have healthy children.This paper reviews the development of PGD technology,the history of its application to hereditary hearing loss,and the general process of how PGD is applied to screen for hereditary hearing loss.The aim of this review is to demonstrate the reliability of PGD in the primary prevention of hereditary hearing loss,assist clinicians in counseling patients at risk of transmitting an inherited disease,and explore the journey from PGD toin vitro fertilization.Given that the application of PGD technology to hereditary hearing loss varies in different countries and regions,there is still a long way to go before PGD is routinely applied for the primary prevention of hereditary hearing loss.