Monogenic diabetes,constituting 1%-2%of global diabetes cases,arises from single gene defects with distinctive inheritance patterns.Despite over 50 associated genetic disorders,accurate diagnoses and management of mon...Monogenic diabetes,constituting 1%-2%of global diabetes cases,arises from single gene defects with distinctive inheritance patterns.Despite over 50 associated genetic disorders,accurate diagnoses and management of monogenic diabetes remain inadequate,underscoring insufficient clinician awareness.The disease spectrum encompasses maturity-onset diabetes of the young(MODY),characterized by distinct genetic mutations affecting insulin secretion,and neonatal diabetes mellitus(NDM)-a heterogeneous group of severe hyperglycemic disorders in infants.Mitochondrial diabetes,autoimmune monogenic diabetes,genetic insulin resistance and lipodystrophy syndromes further diversify the monogenic diabetes landscape.A tailored approach based on phenotypic and biochemical factors to identify candidates for genetic screening is recommended for suspected cases of MODY.NDM diagnosis warrants immediate molecular genetic testing for infants under six months.Identifying these genetic defects presents a unique opportunity for precision medicine.Ongoing research aimed to develop cost-effective genetic testing methods and gene-based therapy can facilitate appropriate identification and optimize clinical outcomes.Identification and study of new genes offer a valuable opportunity to gain deeper insights into pancreatic cell biology and the pathogenic mechanisms underlying common forms of diabetes.The clinical review published in the recent issue of World Journal of Diabetes is such an attempt to fill-in our knowledge gap about this enigmatic disease.展开更多
The first practice of pre-implantation genetic testing(PGT)was reported more than 30 years ago.PGT,originally named preimplantation genetic screening(PGS)and pre-implantation genetic diagnosis(PGD),is now categorized ...The first practice of pre-implantation genetic testing(PGT)was reported more than 30 years ago.PGT,originally named preimplantation genetic screening(PGS)and pre-implantation genetic diagnosis(PGD),is now categorized as PGT for aneuploidies(PGT-A),PGT for monogenic/single-gene defects(PGT-M),and PGT for chromosomal structural rearrangements(PGT-SR).Patients with fertility issues caused by advanced maternal age,carrier status of chromosomal abnormalities,or harboring pathogenic variant(s)are recommended to undergo PGT to increase the possibility of successful live birth and avoid potentially affected newborns.High-throughput techniques,such as DNA microarrays and next-generation sequencing(NGS),have enabled comprehensive screening of all 24 chromosomes,instead of few loci at a time.Furthermore,as a comprehensive PGT,PGT-Plus was enabled by the rapid development of a genome-wide single-cell haplotyping technique to detect embryo aneuploidy,single-gene disorders,and chromosomal aberrations simultaneously using a single universal protocol.In addition,non-invasive approaches enable a more intact embryo during the biopsy procedure,which may avoid potential mosaicism issues at a certain scale by testing spent culture media(SCM).As a novel PGT application,PGT-P detects genome-wide variations in polygenic diseases,which account for a large proportion of premature human deaths and affect a markedly larger population than monogenic diseases,using polygenic risk score calculation to decrease the potential of affecting complex conditions.Owing to the emergence of new technologies recruited to PGTs,more couples with infertility issues have a promising chance of conceiving a healthy baby,ultimately facilitating the human species to live more prosper.展开更多
Invasive genetic screening of pre-implantation embryos via biopsied trophectoderm(TE)cells has been in use for more than 20 years,while its benefits in selecting euploid embryos remain controversial.Recent advances in...Invasive genetic screening of pre-implantation embryos via biopsied trophectoderm(TE)cells has been in use for more than 20 years,while its benefits in selecting euploid embryos remain controversial.Recent advances in the ability to process embryonic cell-free DNA(cfDNA)from blastocoel fluid(BF)and spent culture media(SCM)of blastocysts in a manner similar to that of a biopsied TE sample provide a potential alternative holding great promise for obtaining cytogenetic information of the embryos without intrusive biopsy of traditional biopsy-based pre-implantation genetic testing(PGT).Several studies have reported even higher diagnostic accuracy in non-invasive PGT(ni-PGT)than conventional PGT.However,there are still several technical challenges to be overcome before ni-PGT can be accepted as a reliable genomic information source of embryo.In this review,we have summarized the emergence and current state of ni-PGT,and discussed our own perspectives on their limitations and future prospect.There is still a long way to go before truly wide clinical application of ni-PGT.展开更多
There is increasing evidence that cell-free DNA (cfDNA) in spent culture media (SCM) can be amplified for genetic testing. Therefore, this paper reviews the characteristics of cfDNA, including its fragment size, amoun...There is increasing evidence that cell-free DNA (cfDNA) in spent culture media (SCM) can be amplified for genetic testing. Therefore, this paper reviews the characteristics of cfDNA, including its fragment size, amount, origin, as well as some factors affecting the success rate of its amplification, together to provide researchers with a more comprehensive perspective on embryonic cfDNA. The origin of cfDNA in SCM is complicated and poses challenges to the interpretation of genetic test results. Advanced molecular techniques should distinguish between embryonic and contaminated DNA to maximize the success rate of amplification and analysis. Recent data showed that the type of culture medium, assisted hatching or not, the type of amplification kit, and fresh or thawed embryos were not related to the success rate of amplification, but the length of culture time might affect the success rate. The longer culture time, the more cfDNA is available in the SCM. Then we focused on the concordance between trophectoderm (TE), inner cell mass, whole embryo, and embryonic cfDNA. Despite successful amplification, the concordance between TE and embryonic cfDNA was low. In summary, non-invasive genetic testing using SCM could represent a major advance in future single embryo selection, however, contamination and timing for media collection are key factors affecting the results, and current non-invasive cfDNA testing should not be directly applied to clinical practice. Further research is needed to improve the methods used for testing techniques and genetic analysis to achieve greater accuracy and trace its origins before it can be used in the clinics.展开更多
Autosomal reciprocal translocations represent exchanges of chromatin fragments between non-homologous chromosomes.Translocations are facilitated by the creation of quadrivalent structures during the first meiotic divi...Autosomal reciprocal translocations represent exchanges of chromatin fragments between non-homologous chromosomes.Translocations are facilitated by the creation of quadrivalent structures during the first meiotic division,which are characterized by the length of the translocated and centric segments,asymmetry,and the presence of terminal breakpoints,all of which may impact segregation mode.Here,we report a rare case of multiple reciprocal translocations within a single family.This includes the evaluation of the translocations in each of the spouses and an analysis of their chromosome segregation patterns as determined by the constellation of universal characteristics in each of their quadrivalents.The obtained results will be of interest to fundamental biology,as they will expand the understanding of the factors affecting chromosome segregation during meiosis.展开更多
文摘Monogenic diabetes,constituting 1%-2%of global diabetes cases,arises from single gene defects with distinctive inheritance patterns.Despite over 50 associated genetic disorders,accurate diagnoses and management of monogenic diabetes remain inadequate,underscoring insufficient clinician awareness.The disease spectrum encompasses maturity-onset diabetes of the young(MODY),characterized by distinct genetic mutations affecting insulin secretion,and neonatal diabetes mellitus(NDM)-a heterogeneous group of severe hyperglycemic disorders in infants.Mitochondrial diabetes,autoimmune monogenic diabetes,genetic insulin resistance and lipodystrophy syndromes further diversify the monogenic diabetes landscape.A tailored approach based on phenotypic and biochemical factors to identify candidates for genetic screening is recommended for suspected cases of MODY.NDM diagnosis warrants immediate molecular genetic testing for infants under six months.Identifying these genetic defects presents a unique opportunity for precision medicine.Ongoing research aimed to develop cost-effective genetic testing methods and gene-based therapy can facilitate appropriate identification and optimize clinical outcomes.Identification and study of new genes offer a valuable opportunity to gain deeper insights into pancreatic cell biology and the pathogenic mechanisms underlying common forms of diabetes.The clinical review published in the recent issue of World Journal of Diabetes is such an attempt to fill-in our knowledge gap about this enigmatic disease.
文摘The first practice of pre-implantation genetic testing(PGT)was reported more than 30 years ago.PGT,originally named preimplantation genetic screening(PGS)and pre-implantation genetic diagnosis(PGD),is now categorized as PGT for aneuploidies(PGT-A),PGT for monogenic/single-gene defects(PGT-M),and PGT for chromosomal structural rearrangements(PGT-SR).Patients with fertility issues caused by advanced maternal age,carrier status of chromosomal abnormalities,or harboring pathogenic variant(s)are recommended to undergo PGT to increase the possibility of successful live birth and avoid potentially affected newborns.High-throughput techniques,such as DNA microarrays and next-generation sequencing(NGS),have enabled comprehensive screening of all 24 chromosomes,instead of few loci at a time.Furthermore,as a comprehensive PGT,PGT-Plus was enabled by the rapid development of a genome-wide single-cell haplotyping technique to detect embryo aneuploidy,single-gene disorders,and chromosomal aberrations simultaneously using a single universal protocol.In addition,non-invasive approaches enable a more intact embryo during the biopsy procedure,which may avoid potential mosaicism issues at a certain scale by testing spent culture media(SCM).As a novel PGT application,PGT-P detects genome-wide variations in polygenic diseases,which account for a large proportion of premature human deaths and affect a markedly larger population than monogenic diseases,using polygenic risk score calculation to decrease the potential of affecting complex conditions.Owing to the emergence of new technologies recruited to PGTs,more couples with infertility issues have a promising chance of conceiving a healthy baby,ultimately facilitating the human species to live more prosper.
基金We thank professors Cynthia Casson Morton and Yiping Shen from Harvard Medical School and professor Sharon YC Ruan from Hong Kong Polytechnic University for revising the manuscript.This work was supported by the National Key Research and Development Program of China(2018YFC1005003)the National Natural Science Foundation of China(81974224,81771535)+2 种基金the Natural Science Foundation of Zhejiang Province(LZ18H040001,LQ19H040007)Zhejiang Provincial Key Medical Technology Program(WKJ-ZJ-1826)Zhejiang University Education Foundation Global Partnership Fund.The authors declared no conflict of interest.
文摘Invasive genetic screening of pre-implantation embryos via biopsied trophectoderm(TE)cells has been in use for more than 20 years,while its benefits in selecting euploid embryos remain controversial.Recent advances in the ability to process embryonic cell-free DNA(cfDNA)from blastocoel fluid(BF)and spent culture media(SCM)of blastocysts in a manner similar to that of a biopsied TE sample provide a potential alternative holding great promise for obtaining cytogenetic information of the embryos without intrusive biopsy of traditional biopsy-based pre-implantation genetic testing(PGT).Several studies have reported even higher diagnostic accuracy in non-invasive PGT(ni-PGT)than conventional PGT.However,there are still several technical challenges to be overcome before ni-PGT can be accepted as a reliable genomic information source of embryo.In this review,we have summarized the emergence and current state of ni-PGT,and discussed our own perspectives on their limitations and future prospect.There is still a long way to go before truly wide clinical application of ni-PGT.
基金This review was supported by Shanghai Shen Kang Hospital Development Center Municipal Hospital New Frontier Technology Joint Project(SHDC12017105).
文摘There is increasing evidence that cell-free DNA (cfDNA) in spent culture media (SCM) can be amplified for genetic testing. Therefore, this paper reviews the characteristics of cfDNA, including its fragment size, amount, origin, as well as some factors affecting the success rate of its amplification, together to provide researchers with a more comprehensive perspective on embryonic cfDNA. The origin of cfDNA in SCM is complicated and poses challenges to the interpretation of genetic test results. Advanced molecular techniques should distinguish between embryonic and contaminated DNA to maximize the success rate of amplification and analysis. Recent data showed that the type of culture medium, assisted hatching or not, the type of amplification kit, and fresh or thawed embryos were not related to the success rate of amplification, but the length of culture time might affect the success rate. The longer culture time, the more cfDNA is available in the SCM. Then we focused on the concordance between trophectoderm (TE), inner cell mass, whole embryo, and embryonic cfDNA. Despite successful amplification, the concordance between TE and embryonic cfDNA was low. In summary, non-invasive genetic testing using SCM could represent a major advance in future single embryo selection, however, contamination and timing for media collection are key factors affecting the results, and current non-invasive cfDNA testing should not be directly applied to clinical practice. Further research is needed to improve the methods used for testing techniques and genetic analysis to achieve greater accuracy and trace its origins before it can be used in the clinics.
基金supported by the Ministry of Science and Higher Education of Russian Federation(project“Multicenter research bioresource collection Human Reproductive Health”contract No 075-15-2021-1058 from September 28,2021).
文摘Autosomal reciprocal translocations represent exchanges of chromatin fragments between non-homologous chromosomes.Translocations are facilitated by the creation of quadrivalent structures during the first meiotic division,which are characterized by the length of the translocated and centric segments,asymmetry,and the presence of terminal breakpoints,all of which may impact segregation mode.Here,we report a rare case of multiple reciprocal translocations within a single family.This includes the evaluation of the translocations in each of the spouses and an analysis of their chromosome segregation patterns as determined by the constellation of universal characteristics in each of their quadrivalents.The obtained results will be of interest to fundamental biology,as they will expand the understanding of the factors affecting chromosome segregation during meiosis.
