Drosophila models used to simulate human ATP1A1 gene mutations that cause Charcot-Marie-Tooth type 2 disease and refractory seizures

Certain amino acids changes in the human Na^(+)/K^(+)-ATPase pump,ATPase Na^(+)/K^(+)transporting subunit alpha 1(ATP1A1),cause Charcot-Marie-Tooth disease type 2(CMT2)disease and refractory seizures.To develop in vivo models to study the role of Na^(+)/K^(+)-ATPase in these diseases,we modified the Drosophila gene homolog,Atpα,to mimic the human ATP1A1 gene mutations that cause CMT2.Mutations located within the helical linker region of human ATP1A1(I592T,A597T,P600T,and D601F)were simultaneously introduced into endogenous Drosophila Atpαby CRISPR/Cas9-mediated genome editing,generating the Atpα^(TTTF)model.In addition,the same strategy was used to generate the corresponding single point mutations in flies(Atpα^(I571T),Atpα^(A576T),Atpα^(P579T),and Atpα^(D580F)).Moreover,a deletion mutation(Atpα^(mut))that causes premature termination of translation was generated as a positive control.Of these alleles,we found two that could be maintained as homozygotes(Atpα^(I571T)and Atpα^(P579T)).Three alleles(Atpα^(A576T),Atpα^(P579)and Atpα^(D580F))can form heterozygotes with the Atpαmut allele.We found that the Atpαallele carrying these CMT2-associated mutations showed differential phenotypes in Drosophila.Flies heterozygous for Atpα^(TTTF)mutations have motor performance defects,a reduced lifespan,seizures,and an abnormal neuronal morphology.These Drosophila models will provide a new platform for studying the function and regulation of the sodium-potassium pump.

Mental retardation,seizures and language delay caused by new SETD1B mutations:Three case reports

BACKGROUND The SETD1B gene is instrumental in human intelligence and nerve development.Mutations in the SETD1B gene have been linked in recent studies to neurodevelopmental disorders,seizures,and language delay.CASE SUMMARY This study aimed to analyze the clinical manifestations and treatment of three patients suffering from mental retardation,epilepsy,and language delay resulting from a new mutation in the SETD1B gene.Three individuals with these symptoms were selected,and their clinical symptoms,gene test results,and treatment were analyzed.This article discusses the impact of the SETD1B gene mutation on patients and outlines the treatment approach.Among the three patients(two females and one male,aged 8,4,and 1,respectively),all exhibited psychomotor retardation,attention deficit,and hyperactivity disorder,and two had epilepsy.Antiepileptic treatment with sodium tripolyvalproate halted the seizures in the affected child,although mental development remained somewhat delayed.Whole exome sequencing revealed new mutations in the SETD1B gene for all patients,specifically with c.5473C>T(p.Arg1825trp),c.4120C>T(p.Gln1374*,593),c.14_15insC(p.His5Hisfs*33).CONCLUSION Possessing the SETD1B gene mutation may cause mental retardation accompanied by seizures and language delay.Although the exact mechanism is not fully understood,interventions such as drug therapy,rehabilitation training,and family support can assist patients in managing their symptoms and enhancing their quality of life.Furthermore,genetic testing supplies healthcare providers with more precise diagnostic and therapeutic guidance,informs families about genetic disease risks,and contributes to understanding disease pathogenesis and drug research and development.

Mutational landscape of TP53 and CDH1 in gastric cancer

In this editorial we comment on an article published in a recent issue of the World J Gastrointest Surg.A common gene mutation in gastric cancer(GC)is the TP53 mutation.As a tumor suppressor gene,TP53 is implicated in more than half of all tumor occurrences.TP53 gene mutations in GC tissue may be related with clinical pathological aspects.The TP53 mutation arose late in the progression of GC and aided in the final switch to malignancy.CDH1 encodes E-cadherin,which is involved in cell-to-cell adhesion,epithelial structure maintenance,cell polarity,differentiation,and intracellular signaling pathway modulation.CDH1 mutations and functional loss can result in diffuse GC,and CDH1 mutations can serve as independent prognostic indicators for poor prognosis.GC patients can benefit from genetic counseling and testing for CDH1 mutations.Demethylation therapy may assist to postpone the onset and progression of GC.The investigation of TP53 and CDH1 gene mutations in GC allows for the investigation of the relationship between these two gene mutations,as well as providing some basis for evaluating the prognosis of GC patients.

CHCHD2 Thr61Ile mutation impairs F1F0-ATPase assembly in in vitro and in vivo models of Parkinson's disease

Mitochondrial dysfunction is a significant pathological alte ration that occurs in Parkinson's disease(PD),and the Thr61lle(T61I)mutation in coiled-coil helix coiled-coil helix domain containing 2(CHCHD2),a crucial mitochondrial protein,has been reported to cause Parkinson's disease.FIFO-ATPase participates in the synthesis of cellular adenosine triphosphate(ATP)and plays a central role in mitochondrial energy metabolism.However,the specific roles of wild-type(WT)CHCHD2 and T611-mutant CHCHD2 in regulating F1FO-ATPase activity in Parkinson's disease,as well as whether CHCHD2 or CHCHD2 T61I affects mitochondrial function through regulating F1FO-ATPase activity,remain unclea r.Therefore,in this study,we expressed WT CHCHD2 and T61l-mutant CHCHD2 in an MPP^(+)-induced SH-SY5Y cell model of PD.We found that CHCHD2 protected mitochondria from developing MPP^(+)-induced dysfunction.Under normal conditions,ove rexpression of WT CHCHD2 promoted F1FO-ATPase assembly,while T61I-mutant CHCHD2 appeared to have lost the ability to regulate F1FO-ATPase assembly.In addition,mass spectrometry and immunoprecipitation showed that there was an interaction between CHCHD2 and F1FO-ATPase.Three weeks after transfection with AAV-CHCHD2 T61I,we intraperitoneally injected 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine into mice to establish an animal model of chronic Parkinson's disease and found that exogenous expression of the mutant protein worsened the behavioral deficits and dopaminergic neurodegeneration seen in this model.These findings suggest that WT CHCHD2 can alleviate mitochondrial dysfunction in PD by maintaining F1F0-ATPase structure and function.

Assessment of pathogenicity and functional characterization of APPL1 gene mutations in diabetic patients

BACKGROUND Adaptor protein,phosphotyrosine interacting with PH domain and leucine zipper 1(APPL1)plays a crucial role in regulating insulin signaling and glucose metabolism.Mutations in the APPL1 gene have been associated with the development of maturity-onset diabetes of the young type 14(MODY14).Currently,only two mutations[c.1655T>A(p.Leu552*)and c.281G>A p.(Asp94Asn)]have been identified in association with this disease.Given the limited understanding of MODY14,it is imperative to identify additional cases and carry out comprehensive research on MODY14 and APPL1 mutations.AIM To assess the pathogenicity of APPL1 gene mutations in diabetic patients and to characterize the functional role of the APPL1 domain.METHODS Patients exhibiting clinical signs and a medical history suggestive of MODY were screened for the study.Whole exome sequencing was performed on the patients as well as their family members.The pathogenicity of the identified APPL1 variants was predicted on the basis of bioinformatics analysis.In addition,the pathogenicity of the novel APPL1 variant was preliminarily evaluated through in vitro functional experiments.Finally,the impact of these variants on APPL1 protein expression and the insulin pathway were assessed,and the potential mechanism underlying the interaction between the APPL1 protein and the insulin receptor was further explored.RESULTS A total of five novel mutations were identified,including four missense mutations(Asp632Tyr,Arg633His,Arg532Gln,and Ile642Met)and one intronic mutation(1153-16A>T).Pathogenicity prediction analysis revealed that the Arg532Gln was pathogenic across all predictions.The Asp632Tyr and Arg633His variants also had pathogenicity based on MutationTaster.In addition,multiple alignment of amino acid sequences showed that the Arg532Gln,Asp632Tyr,and Arg633His variants were conserved across different species.Moreover,in in vitro functional experiments,both the c.1894G>T(at Asp632Tyr)and c.1595G>A(at Arg532Gln)mutations were found to downregulate the expression of APPL1 on both protein and mRNA levels,indicating their pathogenic nature.Therefore,based on the patient’s clinical and family history,combined with the results from bioinformatics analysis and functional experiment,the c.1894G>T(at Asp632Tyr)and c.1595G>A(at Arg532Gln)mutations were classified as pathogenic mutations.Importantly,all these mutations were located within the phosphotyrosinebinding domain of APPL1,which plays a critical role in the insulin sensitization effect.CONCLUSION This study provided new insights into the pathogenicity of APPL1 gene mutations in diabetes and revealed a potential target for the diagnosis and treatment of the disease.

TPM1基因在猪背最长肌生长发育过程中的动态表达

【目的】探究原肌球蛋白(tropomyosin,TM)是否在猪背最长肌生长发育过程中发挥生物学功能。【方法】采用SYBR Green Ⅱ荧光法进行荧光定量PCR分析TPM1基因在通城猪和长白猪中的组织表达谱,以及出生前和出生后背最长肌发育中(28个发育点)的表达变化。【结果】TPM1基因在两种猪中背肌和心肌中都有丰富地表达,在背最长肌发育过程中的表达趋势相似,即TPM1基因的表达量先增加后减少,但出现峰值的时间不同(通城猪中,TPM1基因在胚胎期75 d的表达量显著高于其它时间点,P<0.05;长白猪中,TPM1基因在胚胎期90 d的表达量显著高于其它时间点,P<0.05)。【结论】TPM1基因的表达与猪背最长肌生长发育及品种间肌肉表型差异有关。

miRNA-21通过TPM1参与高糖诱导的人主动脉平滑肌细胞表型转化与增殖

目的探讨miRNA-21在高糖诱导的人主动脉平滑肌细胞表型转化与增殖中的作用,以及对靶基因原肌球蛋白1(tropomyosin 1,TPM1)表达的影响。方法体外培养人主动脉平滑肌原代细胞,利用脂质体转染miRNA-21mimic和inhibitor至细胞中,BrdU法检测高糖刺激miRNA-21过表达和缺失情况下人主动脉平滑肌细胞的增殖情况,荧光定量PCR检测转染前后高糖刺激时细胞miRNA-21和TPM1的表达情况,Western blot检测人主动脉平滑肌细胞中TPM1、骨桥蛋白(osteopontin,OPN)、平滑肌蛋白22α(smooth muscle 22alpha,SM22α)的表达情况。结果 10、20、25mmol/L D-葡萄糖刺激时人主动脉平滑肌细胞较正常对照组(0.613±0.022)显著增殖(0.725±0.026、0.913±0.024、1.513±0.082),差异有统计学意义(P<0.01);10、20、25mmol/L D-葡萄糖刺激时miRNA-21表达较对照组升高1.1、2.0、3.1倍(P<0.01);正常组细胞转染miRNA-21mimic后细胞增殖能力增强1.6倍,转染miRNA-21inhibitor后高糖组细胞增殖能力减弱(P<0.01);转染miRNA-21mimic后TPM1表达减弱,SM22α表达下调,OPN表达增加(P<0.01),转染miRNA-21inhibitor后TPM1表达上调,SM22α表达上调,OPN表达减少(P<0.01)。结论 miRNA-21可下调细胞TPM1的表达,从而促进人主动脉平滑肌细胞表型转化与增殖。

TPM1在鼻咽癌中的表达及其临床意义

目的观察TPM1基因的表达与鼻咽癌(NPC)的关系。方法采用实时定量rt-PCR技术检测TPM1基因在NPC细胞株(CNE1、CNE2、58F)和鼻咽上皮细胞株(NP69)中的表达;采用组织芯片技术通过免疫组化检测TPM1在124例恶性鼻咽癌肿瘤、31例对应的癌旁正常组织和12例正常鼻咽黏膜组织的表达。结果 TPM1 mRNA在NP69中表达水平较高,而在NPC细胞株中表达水平显著下降。正常鼻咽黏膜及癌旁组织中TPM1蛋白染色阳性表达率约为65.1%(28/43);而在鼻咽癌组织中阳性表达率约为34.7%(43/124);TPM1蛋白表达水平与肿瘤的侵犯范围(T)呈负相关(P<0.05),与颈淋巴结转移(N)无关(P>0.05)。结论 TPM1基因表达的抑制可能参与鼻咽癌的发生。

TPM1调节口腔鳞癌的增殖、侵袭迁移及其机制研究

目的探讨TPM1在口腔鳞癌组织中的表达情况及对人口腔鳞癌细胞恶性表型的影响。方法通过RT-PCR检测口腔鳞癌组织和癌旁组织标本TPM1的表达情况。选取CLA27和HSC3细胞作为后续实验对象,构建TPM1干扰质粒。采用RT-PCR检测TPM1转染后表达效果,采用CCK-8检测细胞0、24、48和72h增殖情况,划痕实验检测细胞迁移,Transwell检测细胞侵袭能力,Western blot法检测MMP家族蛋白表达情况。结果TPM1在口腔鳞癌组织中高表达(P<0.05)。RT-PCR结果显示敲减组mRNA表达显著低于空载组(P<0.05);过表达组mRNA表达显著高于空载组(P<0.05)。与空载组比较,敲减组细胞增殖、迁移和侵袭能力显著降低(P<0.05);过表达组细胞增殖、迁移和侵袭能力显著增高(P<0.05)。Western blot法检测结果显示,相对于空载组敲减组MMP9蛋白表达水平显著下降(P<0.05);过表达组MMP9蛋白表达水平显著上升(P<0.05)。结论TPM1在口腔鳞癌组织中呈现高表达,TPM1可能通过调节MMP9蛋白显著影响口腔鳞癌细胞的增殖、迁移、侵袭能力。

A novel NF1 frame-shift mutation c.703＿704delTA in a Chinese pedigree with neurofibromatosis type 1

We analyzed the clinical features and NF1 gene mutation in a Chinese pedigree of neurofibromatosis type 1（NF1）. Three members of this family were NF1 patients presenting with different clinical phenotypes and the others were asymptomatic. Exons of NF1 were amplified by polymerase chain reaction, sequenced, compared with a reference database. One novel NF1 frame-shift mutation c.703_704delTA, which resulted in a premature stop signal at codon 720 and the synthesis of truncated, was revealed. This mutation segregated with the NF1 members is likely responsible for the pathogenesis of NF1 in the family.

Infant cholestasis patient with a novel missense mutation in the AKR1D1 gene successfully treated by early adequate supplementation with chenodeoxycholic acid: A case report and review of the literature

Steroid 5β-reductase [aldo-keto reductase family 1 member D1(AKR1D1)] is essential for bile acid biosynthesis. Bile acid deficiency caused by genetic defects in AKR1D1 leads to life-threatening neonatal hepatitis and cholestasis. There is still limited experience regarding the treatment of this disease. We describe an infant who presented with hyperbilirubinemia and coagulopathy but normal bile acid and γ-glutamyltransferase. Gene analysis was performed using genomic DNA from peripheral lymphocytes from the patient, his parents, and his elder brother. The patient was compound heterozygous for c.919C>T in exon 8 and exhibited a loss of heterozygosity of the AKR1D1 gene, which led to an amino acid substitution of arginine by cysteine at amino acid position 307(p.R307C). Based on these mutations, the patient was confirmed to have primary 5β-reductase deficiency. Ursodeoxycholic acid(UDCA) treatment did not have any effect on the patient. However, when we changed to chenodeoxycholic acid(CDCA) treatment, his symptoms and laboratory tests gradually improved. It is therefore crucial to supplement with an adequate dose of CDCA early to improve clinical symptoms and to normalize laboratory tests.

The R1947X mutation of NF1 causing autosomal dominant neurofibromatosis type 1 in a Chinese family

Neurofibromatosis type 1 is a common autosomal dominant disorder with a high rate of penetrance. It is caused by the mutation of the tumor suppressor gene NF1, which encodes neurofibromin. The main function of neurofibromin is down-regulating the biological activity of the proto-oncoprotein Ras by acting as a Ras-specific GTPase activating protein. In this study, we identified a Chinese family affected with neurofibromatosis type 1. The known gene NF1 associated with NF1 was studied by linkage analysis and by direct sequencing of the entire coding region and exon-intron boundaries of the NF1 gene. The R1947X mutation of NF1 was identified, which was co-segregated with affected individuals in the Chinese family, but not present in unaffected family members. This is the first report, which states that the R1947X mutation of NF1 may be one of reasons for neurofibromatosis type 1 in Chinese population.

A novel mutation in FBN1 gene in autosomal dominant Marfan syndrome and macular degeneration in a Chinese consanguineous family

AIM: To report a novel mutation in FBN1 gene in a Chinese consanguineous family with common Marfan syndrome(MFS) phenotype and an unusual bilateral macular degeneration. METHODS: Ophthalmic, cardiovascular and systemic examinations were performed, and genomic DNA extracted from all living family members. The 24-32 exon mutations of FBN1 gene were screened by Sanger Sequencing in all family members and 100 unrelated healthy Chinese individuals. RESULTS: In the four-generation family, classic MFS phenotypes were observed in all 5 patients, 2 of them had peculiar phenotype of bilateral macular degeneration. Mutation screening in FBN1 identified a heterozygous missense mutation(c.3932 A>G, p.Y1311 C) with co-segregation. This mutation was found with the MFS phenotypes in all 5 patients but not in unaffected members or unrelated controls. CONCLUSION: A Chinese consanguineous MFS family with uncommon bilateral macular degeneration and an unreported c.3932 A>G mutation in FBN1 was identified. Our finding expands the FBN1 mutation spectrum and its possible role in the pathogenesis of Marfan syndrome.

Germline MLH1 and MSH2 mutational spectrum including frequent large genomic aberrations in Hungarian hereditary non-polyposis colorectal cancer families:Implications for genetic testing

AIM: To analyze the prevalence of germline MLH1 and MSH2 gene mutations and evaluate the clinical characteristics of Hungarian hereditary non-polyposis colorectal cancer (HNPCC) families. METHODS: Thirty-six kindreds were tested for mutations using conformation sensitive gel electrophoreses, direct sequencing and also screening for genomic rearrangements applying multiplex ligation-dependent probe amplifi cation (MLPA). RESULTS: Eighteen germline mutations (50%) were identifi ed, 9 in MLH1 and 9 in MSH2. Sixteen of these sequence alterations were considered pathogenic, the remaining two were non-conservative missense alterations occurring at highly conserved functional motifs. The majority of the defi nite pathogenic mutations (81%, 13/16) were found in families fulfilling the stringent Amsterdam Ⅰ/Ⅱ criteria, including three rearrangements revealed by MLPA (two in MSH2 and one in MLH1). However, in three out of sixteen HNPCC-suspected families (19%), a disease-causing alteration could be revealed. Furthermore, nine mutations described here are novel, and none of the sequence changes were found in more than one family.CONCLUSION: Our study describes for the f irst time the prevalence and spectrum of germline mismatch repair gene mutations in Hungarian HNPCC and suspected-HNPCC families. The results presented here suggest that clinical selection criteria should be relaxed and detection of genomic rearrangements should be included in genetic screening in this population.

Sex disparity in viral load, inflammation and liver damage in transgenic mice carrying full hepatitis B virus genome with the W4P mutation in the preS1 region

AIM To study sex disparity in susceptibility to hepatocellular carcinoma(HCC), we created a transgenic mouse model that expressed the full hepatitis B virus(HBV) genome with the W4P mutation.METHODS Transgenic mice were generated by transferring the p HY92-1.1 x-HBV-full genome plasmid(genotype A2) into C57 Bl/6 N mice. We compared serum levels of hepatitis B surface antigen(HBs Ag), interleukin(IL)-6, and the liver enzymes alanine aminotransferase(ALT) and aspartate transaminase(AST), as well as liver histopathological features in male and female transgenic(W4PTG) mice and in nontransgenic littermates of 10 mo of age. RESULTS W4PTG males exhibited more pronounced hepatomegaly, significantly increased granule generation in liver tissue, elevated HBs Ag expression in the liver and serum, and higher serum ALT and IL-6 levels compared to W4PTG females or littermate control groups. CONCLUSION Together, our data indicate that the W4 P mutation in pre S1 may contribute to sex disparity in susceptibility to HCC by causing increased HBV virion replication and enhanced IL-6-mediated inflammation in male individuals. Additionally, our transgenic mouse model that expresses full HBV genome with the W4 P mutation in pre S1 could be effectively used for the studies of the progression of liver diseases, including HCC.

Distinctive Drug-resistant Mutation Profiles and Interpretations of HIV-1 Proviral DNA Revealed by Deep Sequencing in Reverse Transcriptase

Objective To investigate distinctive features in drug-resistant mutations （DRMs） and interpretations for reverse transcriptase inhibitors （RTIs） between proviral DNA and paired viral RNA in HIV-l-infected patients. Methods Forty-three HIV-l-infected individuals receiving first-line antiretroviral therapy were recruited to participate in a multicenter AIDS Cohort Study in Anhui and Henan Provinces in China in 2004. Drug resistance genotyping was performed by bulk sequencing and deep sequencing on the plasma and whole blood of 77 samples, respectively. Drug-resistance interpretation was compared between viral RNA and paired proviral DNA. Results Compared with bulk sequencing, deep sequencing could detect more DRMs and samples with DRMs in both viral RNA and proviral DNA. The mutations M1841 and M2301 were more prevalent in proviral DNA than in viral RNA （Fisher＇s exact test, P〈0.05）. Considering ＇majority resistant variants＇, 15 samples （19.48%） showed differences in drug resistance interpretation between viral RNA and proviral DNA, and 5 of these samples with different DRMs between proviral DNA and paired viral RNA showed a higher level of drug resistance to the first-line drugs. Considering ＇minority resistant variants＇, 22 samples （28.57%） were associated with a higher level of drug resistance to the tested RTIs for proviral DNA when compared with paired viral RNA. Conclusion Compared with viral RNA, the distinctive information of DRMs and drug resistance interpretations for proviral DNA could be obtained by deep sequencing, which could provide more detailed and precise information for drug resistance monitoring and the rational design of optimal antiretroviral therapy regimens.

Prevalence and clinical significance of pathogenic germline BRCA1/2 mutations in Chinese non-small cell lung cancer patients

Objective: Germline alterations in the breast cancer susceptibility genes type 1 and 2, BRCA1 and BRCA2, predispose individuals to hereditary cancers, including breast, ovarian, prostate, pancreatic, and stomach cancers.Accumulating evidence suggests inherited genetic susceptibility to lung cancer.The present study aimed to survey the prevalence of pathogenic germline BRCA mutations(gBRCAm) and explore the potential association between gBRCAm and disease onset in Chinese advanced non-small cell lung cancer(NSCLC) patients.Methods: A total of 6,220 NSCLC patients were screened using capture-based ultra-deep targeted sequencing to identify patients harboring germline BRCA1/2 mutations.Results: Out of the 6,220 patients screened, 1.03%(64/6,220) of the patients harbored the pathogenic gB RCAm, with BRCA2 mutations being the most predominant mutations(49/64, 76.5%).Patients who developed NSCLC before 50 years of age were more likely to carry gBRCAm(P = 0.036).Among the patients harboring classic lung cancer driver mutations, those with concurrent gBRCAm were significantly younger than those harboring the wild-type gBRCA(P = 0.029).By contrast, the age of patients with or without concurrent gBRCAm was comparable to those of patients without the driver mutations(P = 0.972).In addition, we identified EGFR-mutant patients with concurrent gBRCAm who showed comparable progression-free survival but significantly longer overall survival(P = 0.002) compared to EGFR-mutant patients with wild-type germline BRCA.Conclusions: Overall, our study is the largest survey of the prevalence of pathogenic gBRCAm in advanced Chinese NSCLC patients.Results suggested a lack of association between germline BRCA status and treatment outcome of EGFR-TKI.In addition,results showed a positive correlation between pathogenic gB RCAm and an early onset of NSCLC.

The interaction between the 2009 H1N1 influenza A hemagglutinin and neuraminidase: mutations, co-mutations, and the NA stalk motifs

As the world is closely watching the current 2009 H1N1 pandemic unfold, there is a great interest and need in understanding its origin, genetic structures, virulence, and pathogenicity. The two surface proteins, hemagglutinin (HA) and neuraminidase (NA), of the influenza virus have been the focus of most flu research due to their crucial biological functions. In our previous study on 2009 H1N1, three aspects of NA were investigated: the mutations and co-mutations, the stalk motifs, and the phylogenetic analysis. In this study, we turned our attention to HA and the interaction between HA and NA. The 118 mutations of 2009 H1N1 HA were found and mapped to the 3D homology model of H1, and the mutations on the five epitope regions on H1 were identified. This information is essential for developing new drugs and vaccine. The distinct response patterns of HA to the changes of NA stalk motifs were discovered, illustrating the functional dependence between HA and NA. With help from our previous results, two co-mutation networks were uncovered, one in HA and one in NA, where each mutation in one network co-mutates with the mutations in the other network across the two proteins HA and NA. These two networks residing in HA and NA separately may provide a functional linkage between the mutations that can impact the drug binding sites in NA and those that can affect the host immune response or vaccine efficacy in HA. Our findings demonstrated the value of conducting timely analysis on the 2009 H1N1 virus and of the integrated approach to studying both surface proteins HA and NA together to reveal their interdependence, which could not be accomplished by studying them individually.

Polycystic kidney and hepatic disease 1 gene mutations in von Meyenburg complexes: Case report

Von Meyenburg complexes(VMCs) are a rare type of ductal plate malformation. We herein report two Chinese families with VMCs, and the suspicious gene mutation of this disease. Proband A was a 62-year-old woman with abnormal echographic presentation of the liver. She received magnetic resonance imaging(MRI) examination and liver biopsy, and the results showed she had VMCs. Histologically proved hepatocellular carcinoma was found 1 year after the diagnosis of VMCs. Proband B was a 57-year-old woman with intrahepatic diffuselesions displayed by abdominal ultrasonography. Her final diagnoses were VMCs, congenital hepatic fibrosis, and hepatitis B surface e antigen-negative chronic hepatitis B after a series of examinations. Then, all the family members of both proband A and proband B were screened for VMCs by MRI or ultrasonography. The results showed that four of the 11 family members from two families, including two males and two females, were diagnosed with VMCs. DNA samples were extracted from the peripheral blood of those 11 individuals of two VMCs pedigrees and subjected to polymerase chain reaction amplification of the polycystic kidney and hepatic disease 1(PKHD1) gene. Two different mutation loci were identified. Heterozygous mutations located in exon 32(c.4280 delG, p.Gly1427 ValfsX 6) in family A and exon 28(c.3118 C>T, p.Arg1040 Ter) in family B were detected. We speculate that PKHD1 gene mutations may be responsible for the development of VMCs.

Detection of germline mutations of hMLH1 and hMSH2 based on cDNA sequencing in China

AIM： TO detect the germline mutations Of hMLH1 and hMSH2 based on mRNA sequencing to identify hereditary non polyposis oolorectal cancer （HNPCC） families. METHODS： Total RNA was extracted from peripberal blood of 14 members from 12 different families fulfilling Amsterdam criteria II. mRNA of hMLH1 and hMSH2 was reversed with special primers and heat-resistant reverse tmnscriptase, cDNA was amplified with expand long template PCR and cDNA sequendng analysis was followed. RESULT： Seven germline mutations were found in 6 families （6/12, 50%）, in 4 hMLH1 and 3 hMSH2 mutations （4/12, 33.3%）; （3/12, 25%）. The mutation types involved 4 missense, 1 silent and 1 frame shift mutations as well as 1 mutation in the non-coding area. Four out of the seven mutations have not been reported previously. The 4 hMLH1 mutations were distributed in exons 8, 12, 16, and 19. The 3 hMSH2 mutations were distributed in exons 1 and 2. Six out of the 7 mutations were pathological, which were dislTibuted in 5 HNPCC families. CONCLUSION： Germline mutations of hMLH1 and hMSH2 can be found based on cDNA sequencing so as to identify HNPCC family, which is highly sensitive and has the advantages of cost and time saving.