Hereditary hearing loss(HHL),a genetic disorder that impairs auditory function,significantly affects quality of life and incurs substantial economic losses for society.To investigate the underlying causes of HHL and e...Hereditary hearing loss(HHL),a genetic disorder that impairs auditory function,significantly affects quality of life and incurs substantial economic losses for society.To investigate the underlying causes of HHL and evaluate therapeutic outcomes,appropriate animal models are necessary.Pigs have been extensively used as valuable large animal models in biomedical research.In this review,we highlight the advantages of pig models in terms of ear anatomy,inner ear morphology,and electrophysiological characteristics,as well as recent advancements in the development of distinct genetically modified porcine models of hearing loss.Additionally,we discuss the prospects,challenges,and recommendations regarding the use pig models in HHL research.Overall,this review provides insights and perspectives for future studies on HHL using porcine models.展开更多
Hereditary vitamin D-resistant rickets (HVDRR) is a rare autosomal recessive disorder characterized by severe rickets, hypocalcemia, hypophosphatemia, secondary hyperparathyroidism, and elevated alkaline phosphatase...Hereditary vitamin D-resistant rickets (HVDRR) is a rare autosomal recessive disorder characterized by severe rickets, hypocalcemia, hypophosphatemia, secondary hyperparathyroidism, and elevated alkaline phosphatase. This disorder is caused by homogeneous or heterogeneous mutations affecting the function of the vitamin D receptor (VDR), which lead to complete or partial target organ resistance to the action of 1,25- dihydroxy vitamin D~ A non-consanguineous family of Chinese Han origin with one affected individual demonstrating HVDRR was recruited, with the proband evaluated clinically, biochemically and radiographically. To identify the presence of mutations in the VDR gene, all the exons and exon-intron junctions of the VDR gene from all family members were amplified using PCR and sequenced. The proband showed rickets, progressive alopecia, hypocalcemia, hypophosphatemia, secondary hyperparathyroidism, and elevated alkaline phosphatase. She also suffered from epilepsy, which is rarely seen in patients with HVDRR. Direct sequencing analysis revealed a homozygous missense mutation c.122G 〉 A (p.C41Y) in the VDR gene of the proband, which is located in the first zinc finger of the DNA-binding domain. Both parents had a normal phenotype and were found to be heterozygous for this mutation. We report a Chinese Han family with one individual affected with HVDRR. A homozygous missense mutation c.122G 〉 A (p.C41Y) in the VDR gene was found to be responsible for the patient's syndrome. In contrast to the results of treatment of HVDRR in other patients, our patient responded well to a supplement of oral calcium and a low dose of calcitriol.展开更多
Objective To understand the genetic load in the Chinese population for improvement in diagnosis, prevention and rehabilitation of deafness. Methods DNA samples, immortalized cell lines as well as detailed clinical and...Objective To understand the genetic load in the Chinese population for improvement in diagnosis, prevention and rehabilitation of deafness. Methods DNA samples, immortalized cell lines as well as detailed clinical and audiometric data were collected through a national genetic resources collecting network. Two conventional genetic approaches were used in the studies. Linkage analysis in X chromosome and autosomes with microsatellite markers were performed in large families for gene mapping and positional cloning of novel genes. Candidate gene approach was used for screening the mtDNA 12SrRNA, GJB2 and SLC26A4 mutations in population -based samples. Results A total of 2,572 Chinese hearing loss families or sporadic cases were characterized in the reported studies, including seven X-linked, one Y-linked, 28 large and multiplex autosomal dominant hearing loss families, 607 simplex autosomal recessive hereditary hearing loss families, 100 mitochondrial inheritance families, 147 GJB2 induced hearing loss cases, 230 cases with enlarged vestibular aqueduct (EVA) syndrome, 169 sporadic cases with auditory neuropathy, and 1,283 sporadic sensorineural hearing loss cases. Through linkage analysis or sequence analysis, two X-linked families were found transmitting two novel mutations in the POU3F4 gene, while another X -linked family was mapped onto a novel locus, nominated as AUNX1 (auditory neuropathy, X-linked locus 1). The only Y-linked family was mapped onto the DFNY1 locus(Y-linked locus 1, DFNY1). Eight of the 28 autosomal dominant families were linked to various autosomal loci. In population genetics studies, 2,567 familial cases and sporadic patients were subjected to mutation screening for three common hearing loss genes: mtDNA 12S rRNA 1555G, GJB2 and SLC26A4. The auditory neuropathy cases in our samples were screened for OTOF gene mutations. Conclusions These data show that the Chinese population has a genetic load on hereditary hearing loss. Establishing personalized surveillance and prevention models for hearing loss based on genetic research will provide the opportunity to decrease the prevalence of deafness in the Chinese population.展开更多
The introduction of next-generation sequencing(NGS) technology in testing for hereditary cancer susceptibility allows testing of multiple cancer susceptibility genes simultaneously. While there are many potential bene...The introduction of next-generation sequencing(NGS) technology in testing for hereditary cancer susceptibility allows testing of multiple cancer susceptibility genes simultaneously. While there are many potential benefits to utilizing this technology in the hereditary cancer clinic, including efficiency of time and cost, there are also important limitations that must be considered. The best panel for the given clinical situation should be selected to minimize the number of variants of unknown significance. The inclusion in panels of low penetrance or newly identified genes without specific actionability can be problematic for interpretation.Genetic counselors are an essential part of the hereditary cancer risk assessment team, helping the medical team select the most appropriate test and interpret the often complex results. Genetic counselors obtain an extended family history, counsel patients on the available tests and the potential implications of results for themselves and their family members(pre-test counseling), explain to patients the implications of the test results(post-test counseling), and assist in testing family members at risk.展开更多
BACKGROUND Hereditary spastic paraplegia(HSP)is a group of neurogenetic diseases of the corticospinal tract,accompanied by distinct spasticity and weakness of the lower extremities.Mutations in the spastic paraplegia ...BACKGROUND Hereditary spastic paraplegia(HSP)is a group of neurogenetic diseases of the corticospinal tract,accompanied by distinct spasticity and weakness of the lower extremities.Mutations in the spastic paraplegia type 4(SPG4)gene,encoding the spastin protein,are the major cause of the disease.This study reported a Chinese family with HSP caused by a novel mutation of the SPG4 gene.CASE SUMMARY A 44-year-old male was admitted to our hospital for long-term right lower limb weakness,leg stiffness,and unstable walking.His symptoms gradually worsened,while no obvious muscle atrophy in the lower limbs was found.Neurological examinations revealed that the muscle strength of the lower limbs was normal,and knee reflex hyperreflexia and bilateral positive Babinski signs were detected.Members of his family also had the same symptoms.Using mutation analysis,a novel heterozygous duplication mutation,c.1053dupA,p.(Gln352Thrfs*15),was identified in the SPG4 gene in this family.CONCLUSION A Chinese family with HSP had a novel mutation of the SPG4 gene,which is autosomal dominant and inherited as pure HSP.The age of onset,sex distribution,and clinical manifestations of all existing living patients in this family were analyzed.The findings may extend the current knowledge on the existing mutations in the SPG4 gene.展开更多
目的分析枣庄市4129例孕妇常见耳聋基因突变位点筛查结果,探讨枣庄市孕期女性常见耳聋基因突变分布特点及耳聋基因筛查的临床意义。方法选取2020年10月至2022年4月就诊于枣庄市妇幼保健院进行耳聋基因筛查的4129例孕妇为研究对象,经知...目的分析枣庄市4129例孕妇常见耳聋基因突变位点筛查结果,探讨枣庄市孕期女性常见耳聋基因突变分布特点及耳聋基因筛查的临床意义。方法选取2020年10月至2022年4月就诊于枣庄市妇幼保健院进行耳聋基因筛查的4129例孕妇为研究对象,经知情同意后采集外周血,利用高通量测序法检测18个耳聋相关基因共100个突变位点,分析各突变位点的检出率及分布情况。对耳聋基因携带者孕妇的配偶进行基因测序,并对孕妇妊娠结局进行随访。结果在4129例受检者中,共检出311例携带耳聋基因突变,总体突变携带率为7.53%。其中,GJB2突变携带者140例(3.39%),SLC26A4突变携带者105例(2.54%),GJB3突变携带者21例(0.51%),线粒体12S rRNA突变携带者34例(0.82%),TMC1突变携带者1例(0.02%),纯合或复合杂合突变者4例(0.10%),双基因突变携带者6例(0.15%)。线粒体12S rRNA基因突变者均未出现听力缺失,其新生儿也均通过了听力筛查。结论在枣庄市孕期女性常见耳聋基因突变位点中,阳性检出率较高的3种变异分别是GJB2235 del C(2.47%)、SLC26A4 IVS7-2 A>G(1.24%)和GJB2299 del AT(0.63%)。线粒体12S rRNA基因突变者均未出现听力缺失,与目前临床对氨基糖苷类药物的控制使用有关。针对产前孕妇进行耳聋基因热点变异筛查,明确本地区耳聋基因突变的人群特点,对有效实现遗传性耳聋的二级预防具有重要意义。展开更多
Preimplantation genetic testing(PGT),which was developed as an alternative to prenatal genetic testing,allows couples to avoid pregnancies with abnormal chromosomes and the subsequent termination of the affected fetus...Preimplantation genetic testing(PGT),which was developed as an alternative to prenatal genetic testing,allows couples to avoid pregnancies with abnormal chromosomes and the subsequent termination of the affected fetus.Originally used for early onset monogenic conditions,PGT is now used to prevent various types of inherited cancer conditions based on the development of PGT technology,assisted reproductive techniques(ARTs),and in vitro fertilization(IVF).This review provides insights into the potential benefits and challenges associated with the application of PGT for hereditary cancer and provides an overview of the existing literature on this test,with a particular focus on the current challenges related to laws,ethics,counseling,and technology.Additionally,this review predicts the future potential applications of this method.Although PGT may be utilized to predict and prevent hereditary cancer,each case should be comprehensively evaluated.The motives of couples must be assessed to prevent the misuse of this technique for eugenic purposes,and non-pathogenic phenotypes must be carefully evaluated.Pathological cases that require this technology should also be carefully considered based on legal and ethical reasoning.PGT may be the preferred treatment for hereditary cancer cases;however,such cases require careful case-by-case evaluations.Therefore,this study concludes that multidisciplinary counseling and support for patients and their families are essential to ensure that PGT is a viable option that meets all legal and ethical concerns.展开更多
Hearing loss(HL) is one of the most widespread sensory disorders,affecting approximately 1 in 500 newborns.Heritable diseases of the inner ear are the leading causes of prelingual HL.Treating of hereditary HL and unde...Hearing loss(HL) is one of the most widespread sensory disorders,affecting approximately 1 in 500 newborns.Heritable diseases of the inner ear are the leading causes of prelingual HL.Treating of hereditary HL and understanding its underlying mechanisms remain difficult challenges to otolaryngologists.As stem cells are capable of self-renewal and differentiation,they are ideally suited both for disease modeling and regenerative medicine.Recently,description of induced pluripotent stem cells(iPSCs) has allowed the field of disease modeling and personalized therapy to become far more accessible and physiologically relevant,as iPSCs can be generated from patients of any genetic background.This review briefly describes the advantages of iPSCs technology and discusses potential applications of this powerful biological tool in studying and treating hereditary HL.展开更多
AIM: To study the clinicopathological and molecular genetic characteristics of typical Chinese hereditary nonpolyposis cotorectal cancer (HNPCC) families. METHODS: Four typical Chinese HNPCC families were analyzed usi...AIM: To study the clinicopathological and molecular genetic characteristics of typical Chinese hereditary nonpolyposis cotorectal cancer (HNPCC) families. METHODS: Four typical Chinese HNPCC families were analyzed using microdissection, microsatellite instability analysis, immunostaining of hMSH2 and hMLH1 proteins and direct DNA sequencing of hMSH2 and hMLH1 genes. RESULTS: All five tumor tissues of 4 probands from the 4 typical Chinese HNPCC families showed microsatellite instability at more than two loci (MSI-H or RER+ phenotype). Three out of the 4 cases lost hMSH2 protein expression and the other case showed no hMLH1 protein expression. Three pathological germline mutations (2 in hMSH2 and 1 in hMLH1), which had not been reported previously, were identified. The same mutations were also found in other affected members of two HNPCC families,respectively. CONCLUSION: Typical Chinese HNPCC families showed relatively frequent germline mutation of mismatch repair genes. High-level microsatellite instability and loss of expression of mismatch repair genes correlated closely with germline mutation of mismatch repair genes. Microsatellite instability analysis and immunostaining of mismatch repair gene might serve as effective screening methods before direct DNA sequencing. It is necessary to establish clinical criteria and molecular diagnostic strategies more suitable for Chinese HNPCC families.展开更多
基金supported by the National Key Research and Development Program of China (2021YFA0805902,2022YFF0710703)National Natural Science Foundation of China (32201257)+1 种基金Science and Technology Innovation Project of Xiongan New Area (2022XAGG0121)Young Elite Scientists Sponsorship Program by the China Association for Science and Technology (2019QNRC001)。
文摘Hereditary hearing loss(HHL),a genetic disorder that impairs auditory function,significantly affects quality of life and incurs substantial economic losses for society.To investigate the underlying causes of HHL and evaluate therapeutic outcomes,appropriate animal models are necessary.Pigs have been extensively used as valuable large animal models in biomedical research.In this review,we highlight the advantages of pig models in terms of ear anatomy,inner ear morphology,and electrophysiological characteristics,as well as recent advancements in the development of distinct genetically modified porcine models of hearing loss.Additionally,we discuss the prospects,challenges,and recommendations regarding the use pig models in HHL research.Overall,this review provides insights and perspectives for future studies on HHL using porcine models.
基金supported by a grant from The Ministry of Science and Technology of the People’s Republic of China(National Science and Technology Major Projects for "Major New Drugs Innovation and Development" 2008ZX09312-016)National Natural Science Foundation of China (no.81070687 and 81170805)+2 种基金Beijing Natural Science Foundation (no.7121012)Scientific Research Foundation of Beijing Medical Development (no.2007-3029)National Key Program of Clinical Science (WBYZ2011-873)
文摘Hereditary vitamin D-resistant rickets (HVDRR) is a rare autosomal recessive disorder characterized by severe rickets, hypocalcemia, hypophosphatemia, secondary hyperparathyroidism, and elevated alkaline phosphatase. This disorder is caused by homogeneous or heterogeneous mutations affecting the function of the vitamin D receptor (VDR), which lead to complete or partial target organ resistance to the action of 1,25- dihydroxy vitamin D~ A non-consanguineous family of Chinese Han origin with one affected individual demonstrating HVDRR was recruited, with the proband evaluated clinically, biochemically and radiographically. To identify the presence of mutations in the VDR gene, all the exons and exon-intron junctions of the VDR gene from all family members were amplified using PCR and sequenced. The proband showed rickets, progressive alopecia, hypocalcemia, hypophosphatemia, secondary hyperparathyroidism, and elevated alkaline phosphatase. She also suffered from epilepsy, which is rarely seen in patients with HVDRR. Direct sequencing analysis revealed a homozygous missense mutation c.122G 〉 A (p.C41Y) in the VDR gene of the proband, which is located in the first zinc finger of the DNA-binding domain. Both parents had a normal phenotype and were found to be heterozygous for this mutation. We report a Chinese Han family with one individual affected with HVDRR. A homozygous missense mutation c.122G 〉 A (p.C41Y) in the VDR gene was found to be responsible for the patient's syndrome. In contrast to the results of treatment of HVDRR in other patients, our patient responded well to a supplement of oral calcium and a low dose of calcitriol.
基金supported by grants from the National High Tech Development Project (No. 2006AA028 Z181)the National Natural Science Foundation of China,Key Project (No. 30830104)+5 种基金the National Natural Science Foundation of China(No. 30771857, 30672310 & 30771203)the Foundation of National Excellent Doctoral Thesis (No. 200463)Beijing Nature Science Technology Major Project (No. D0906005 040291 & 7070002)the National 973 Project (No. 2007CB 507400)as well as the National Eleventh Scientific Program (No. 2006BAI02B06& 2007BAI18B12)the Sun Yat-Sen University Start-up Fund (Grant No. 3171310)
文摘Objective To understand the genetic load in the Chinese population for improvement in diagnosis, prevention and rehabilitation of deafness. Methods DNA samples, immortalized cell lines as well as detailed clinical and audiometric data were collected through a national genetic resources collecting network. Two conventional genetic approaches were used in the studies. Linkage analysis in X chromosome and autosomes with microsatellite markers were performed in large families for gene mapping and positional cloning of novel genes. Candidate gene approach was used for screening the mtDNA 12SrRNA, GJB2 and SLC26A4 mutations in population -based samples. Results A total of 2,572 Chinese hearing loss families or sporadic cases were characterized in the reported studies, including seven X-linked, one Y-linked, 28 large and multiplex autosomal dominant hearing loss families, 607 simplex autosomal recessive hereditary hearing loss families, 100 mitochondrial inheritance families, 147 GJB2 induced hearing loss cases, 230 cases with enlarged vestibular aqueduct (EVA) syndrome, 169 sporadic cases with auditory neuropathy, and 1,283 sporadic sensorineural hearing loss cases. Through linkage analysis or sequence analysis, two X-linked families were found transmitting two novel mutations in the POU3F4 gene, while another X -linked family was mapped onto a novel locus, nominated as AUNX1 (auditory neuropathy, X-linked locus 1). The only Y-linked family was mapped onto the DFNY1 locus(Y-linked locus 1, DFNY1). Eight of the 28 autosomal dominant families were linked to various autosomal loci. In population genetics studies, 2,567 familial cases and sporadic patients were subjected to mutation screening for three common hearing loss genes: mtDNA 12S rRNA 1555G, GJB2 and SLC26A4. The auditory neuropathy cases in our samples were screened for OTOF gene mutations. Conclusions These data show that the Chinese population has a genetic load on hereditary hearing loss. Establishing personalized surveillance and prevention models for hearing loss based on genetic research will provide the opportunity to decrease the prevalence of deafness in the Chinese population.
文摘The introduction of next-generation sequencing(NGS) technology in testing for hereditary cancer susceptibility allows testing of multiple cancer susceptibility genes simultaneously. While there are many potential benefits to utilizing this technology in the hereditary cancer clinic, including efficiency of time and cost, there are also important limitations that must be considered. The best panel for the given clinical situation should be selected to minimize the number of variants of unknown significance. The inclusion in panels of low penetrance or newly identified genes without specific actionability can be problematic for interpretation.Genetic counselors are an essential part of the hereditary cancer risk assessment team, helping the medical team select the most appropriate test and interpret the often complex results. Genetic counselors obtain an extended family history, counsel patients on the available tests and the potential implications of results for themselves and their family members(pre-test counseling), explain to patients the implications of the test results(post-test counseling), and assist in testing family members at risk.
基金Supported by The Shandong Provincial Natural Science Foundation,No.ZR2021MH059。
文摘BACKGROUND Hereditary spastic paraplegia(HSP)is a group of neurogenetic diseases of the corticospinal tract,accompanied by distinct spasticity and weakness of the lower extremities.Mutations in the spastic paraplegia type 4(SPG4)gene,encoding the spastin protein,are the major cause of the disease.This study reported a Chinese family with HSP caused by a novel mutation of the SPG4 gene.CASE SUMMARY A 44-year-old male was admitted to our hospital for long-term right lower limb weakness,leg stiffness,and unstable walking.His symptoms gradually worsened,while no obvious muscle atrophy in the lower limbs was found.Neurological examinations revealed that the muscle strength of the lower limbs was normal,and knee reflex hyperreflexia and bilateral positive Babinski signs were detected.Members of his family also had the same symptoms.Using mutation analysis,a novel heterozygous duplication mutation,c.1053dupA,p.(Gln352Thrfs*15),was identified in the SPG4 gene in this family.CONCLUSION A Chinese family with HSP had a novel mutation of the SPG4 gene,which is autosomal dominant and inherited as pure HSP.The age of onset,sex distribution,and clinical manifestations of all existing living patients in this family were analyzed.The findings may extend the current knowledge on the existing mutations in the SPG4 gene.
文摘目的分析枣庄市4129例孕妇常见耳聋基因突变位点筛查结果,探讨枣庄市孕期女性常见耳聋基因突变分布特点及耳聋基因筛查的临床意义。方法选取2020年10月至2022年4月就诊于枣庄市妇幼保健院进行耳聋基因筛查的4129例孕妇为研究对象,经知情同意后采集外周血,利用高通量测序法检测18个耳聋相关基因共100个突变位点,分析各突变位点的检出率及分布情况。对耳聋基因携带者孕妇的配偶进行基因测序,并对孕妇妊娠结局进行随访。结果在4129例受检者中,共检出311例携带耳聋基因突变,总体突变携带率为7.53%。其中,GJB2突变携带者140例(3.39%),SLC26A4突变携带者105例(2.54%),GJB3突变携带者21例(0.51%),线粒体12S rRNA突变携带者34例(0.82%),TMC1突变携带者1例(0.02%),纯合或复合杂合突变者4例(0.10%),双基因突变携带者6例(0.15%)。线粒体12S rRNA基因突变者均未出现听力缺失,其新生儿也均通过了听力筛查。结论在枣庄市孕期女性常见耳聋基因突变位点中,阳性检出率较高的3种变异分别是GJB2235 del C(2.47%)、SLC26A4 IVS7-2 A>G(1.24%)和GJB2299 del AT(0.63%)。线粒体12S rRNA基因突变者均未出现听力缺失,与目前临床对氨基糖苷类药物的控制使用有关。针对产前孕妇进行耳聋基因热点变异筛查,明确本地区耳聋基因突变的人群特点,对有效实现遗传性耳聋的二级预防具有重要意义。
文摘Preimplantation genetic testing(PGT),which was developed as an alternative to prenatal genetic testing,allows couples to avoid pregnancies with abnormal chromosomes and the subsequent termination of the affected fetus.Originally used for early onset monogenic conditions,PGT is now used to prevent various types of inherited cancer conditions based on the development of PGT technology,assisted reproductive techniques(ARTs),and in vitro fertilization(IVF).This review provides insights into the potential benefits and challenges associated with the application of PGT for hereditary cancer and provides an overview of the existing literature on this test,with a particular focus on the current challenges related to laws,ethics,counseling,and technology.Additionally,this review predicts the future potential applications of this method.Although PGT may be utilized to predict and prevent hereditary cancer,each case should be comprehensively evaluated.The motives of couples must be assessed to prevent the misuse of this technique for eugenic purposes,and non-pathogenic phenotypes must be carefully evaluated.Pathological cases that require this technology should also be carefully considered based on legal and ethical reasoning.PGT may be the preferred treatment for hereditary cancer cases;however,such cases require careful case-by-case evaluations.Therefore,this study concludes that multidisciplinary counseling and support for patients and their families are essential to ensure that PGT is a viable option that meets all legal and ethical concerns.
基金supported by grants from National Basic Research Program of China(the 973 Project,grant numbers: 2012CB967904 and 2012CB967900)the Cochlear Implantation Program of Hunan,China
文摘Hearing loss(HL) is one of the most widespread sensory disorders,affecting approximately 1 in 500 newborns.Heritable diseases of the inner ear are the leading causes of prelingual HL.Treating of hereditary HL and understanding its underlying mechanisms remain difficult challenges to otolaryngologists.As stem cells are capable of self-renewal and differentiation,they are ideally suited both for disease modeling and regenerative medicine.Recently,description of induced pluripotent stem cells(iPSCs) has allowed the field of disease modeling and personalized therapy to become far more accessible and physiologically relevant,as iPSCs can be generated from patients of any genetic background.This review briefly describes the advantages of iPSCs technology and discusses potential applications of this powerful biological tool in studying and treating hereditary HL.
基金Supported by the Shanghai Medical Development Project,No.993025
文摘AIM: To study the clinicopathological and molecular genetic characteristics of typical Chinese hereditary nonpolyposis cotorectal cancer (HNPCC) families. METHODS: Four typical Chinese HNPCC families were analyzed using microdissection, microsatellite instability analysis, immunostaining of hMSH2 and hMLH1 proteins and direct DNA sequencing of hMSH2 and hMLH1 genes. RESULTS: All five tumor tissues of 4 probands from the 4 typical Chinese HNPCC families showed microsatellite instability at more than two loci (MSI-H or RER+ phenotype). Three out of the 4 cases lost hMSH2 protein expression and the other case showed no hMLH1 protein expression. Three pathological germline mutations (2 in hMSH2 and 1 in hMLH1), which had not been reported previously, were identified. The same mutations were also found in other affected members of two HNPCC families,respectively. CONCLUSION: Typical Chinese HNPCC families showed relatively frequent germline mutation of mismatch repair genes. High-level microsatellite instability and loss of expression of mismatch repair genes correlated closely with germline mutation of mismatch repair genes. Microsatellite instability analysis and immunostaining of mismatch repair gene might serve as effective screening methods before direct DNA sequencing. It is necessary to establish clinical criteria and molecular diagnostic strategies more suitable for Chinese HNPCC families.