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1.
Smith-Fineman-Myers综合征基因定位于Xq25   总被引:4,自引:2,他引:4  
目的 定位 Smith Finem an Myers 综合征基因,为分离该基因奠定基础。方法 应用覆盖 X染色体全长的、具有多态性的短串联重复序列( S T R) 对 X 染色体进行扫查,确定致病基因所在区域和与致病基因连锁的 S T R 位点,再对该位点两侧的 S T R 位点进行分析,确定致病基因的精确位置。结果 用20个覆盖 X 染色体全长的、具有多态性的 S T R 位点对该综合征患者家系中的13 个能明确提供连锁分析信息的家系成员进行分析,发现位于 Xq25 上的 D X S1001 与致病基因紧密连锁,最大两点lods 得分为301(θ= 0) ,对 D X S1001 两侧的 S T R 分析证实,该致病基因位于 D X S1001 区域,单体型分析表明该致病基因位于 D X S8064 和 D X S8050 之间,区域为146c M。结论  Smith Finem an Myers 综合征基因,位于 Xq25 上的 D X S8064 和 D X S8050 之间的146c M 区域,该基因的定位为分离该基因奠定了基础。  相似文献   

2.
Fanconi anemia (FA) is a rare autosomal recessive disease characterized by progressive pancytopenia, congenital malformations, and predisposition to acute myeloid leukemia. Fanconi anemia is genetically heterogeneous, with at least eight distinct complementation groups of FA (A, B, C, D1, D2, E, F, and G) having been defined by somatic cell fusion studies. Six genes (FANCA, FANCC, FANCD2, FANCE, FANCG, and FANCF) have been cloned. Mutations of the seventh Fanconi anemia gene, BRCA2, have been shown to lead to FAD1 and probably FAB groups. In order to characterize the molecular defects underlying FA in Tunisia, 39 families were genotyped with microsatellite markers linked to known FA gene. Haplotype analysis and homozygosity mapping assigned 43 patients belonging to 34 families to the FAA group, whereas one family was probably not linked to the FANCA gene or to any known FA genes. For patients belonging to the FAA group, screening for mutations revealed four novel mutations: two small homozygous deletions 1693delT and 1751–1754del, which occurred in exon 17 and exon 19, respectively, and two transitions, viz., 513GA in exon 5 and AG at position 166 (IVS24+166AG) of intron 24. Two new polymorphisms were also identified in intron 24 (IVS24–5G/A and IVS24–6C/G).C. Bouchlaka, S. Abdelhak, A. Amouri, N. Labbane, S. Chakroun, M. Benfadhel, K. Dellagi, L. Aissaoui, R. Belakhal, Z. Belhaj Ali, H. Ben Abid, B. Meddeb, A. Hafsia, M. Elloumi, S. Hadiji, M. Frikha, F. Fakhfakh, H. Ayadi, M. Hachicha, A. Abdelkafi, L. Tordjman, F. Mellouli, T. Ben Othman, S. Ladeb, A. Ben Abdeladhim, H. Sennana, H. Elghezal, A. Saad, H. Elomri, A. Laatiri, A. Khelif, S. Ennabli, F. Amri, M. Trudi, and A. Rebaï belong to the Tunisian Fanconi Anemia Study Group  相似文献   

3.
 The incidence of congenital preauricular fistula (CPF) is >1.1% in both Chinese and Caucasians, but it is even higher in Blacks. We mapped the locus for CPF to chromosome 8q11.1–q13.3 by linkage analysis of a family composed of 7 affected and 11 nonaffected members. The two-point LOD score was 2.40, shown by markers D8S285 and D8S1113 at a recombination fraction (θ) of 0.00. Results from three other markers (D8S1110, D8S260, and D8S1136) in the same region further support the linkage. Haplotype analysis for this family confined the locus to within an interval of approximately 26.7 cM, flanked by markers D8S532 and D8S279. A LOD score of <3 is likely due to the limitation of family size. Received: October 16, 2002; Accepted: November 25, 2002 Acknowledgments We would like to thank Shanghai Municipal Commission for Science and Technology, the National Natural Science Foundation of China, and the National 973 and 863 Projects for their generous financial support of this study. The first and third authors contributed equally to this work. Correspondence to:L. He  相似文献   

4.
Liver transplantation has been considered as a promising therapy to halt the progression of clinical symptoms in familial amyloidotic polyneuropathy (FAP) because most transthyretin (TTR) is produced by the liver. In addition, domino liver transplantation using an FAP patient’s liver has been performed because of a shortage of donor livers. However, because the use of liver transplantation as therapy for FAP has given rise to several problems, an alternative treatment is needed. We have tried several other approaches. Recent studies suggested that certain metal ions affect amyloidogenesis. Among metal ions tested in an in vitro amyloid formation study, Cr3+ increased stability of both normal and mutant TTR tetramers and suppressed TTR amyloidogenesis induced by low pH. Our findings indicate that Cr3+ acts to suppress TTR amyloidogenesis. BSB, a Congo red derivative that binds to amyloid fibrils in FAP as well as to those in senile plaques in Alzheimer’s disease, effectively suppressed TTR amyloid formation in vitro. BSB may thus be useful for preventing amyloid formation. Free radical scavenger therapy was also tried in FAP patients but yielded no conclusive results. Immunization for transgenic mice having the ATTR V30M gene using ATTR Y78P resulted in suppression of amyloid deposits. Finally, an RNA/DNA chimera and single-stranded oligonucleotides (SSOs) were tested in vitro and in vivo in an attempt to repair the amyloidogenic TTR gene in the liver and retina. On the basis of results achieved so far, SSO is a promising tool for gene therapy.  相似文献   

5.
Chemoprevention, prophylactic surgery and intensified screening programs are options which can be offered the patients with an increased lifetime risk (p(life)) for breast cancer (BC). Estimation of p(life) includes BRCA mutation analysis and risk estimation based on individual risk factors and family history. MENDEL and BRCAPRO are models which can estimate mutation carrier status probability (p(mut)), p(life) and p(mut) can be estimated using Cyrillic3 software which incorporates BRCAPRO and MENDEL. To integrate age, hormonal factors and benign breast biopsies in risk assessment the Tyrer-Cuzick model can be used. These models support the decision pro or contra genetic analysis and improve the number of positive gene testing results. Estimations of p(life) and p(mut), based on a mathematical model, should deal with algorithms and penetrance/frequency data adequate to the population counselled. Being the main modulatory factors, reproductive/hormonal data should be incorporated like the Tyrer-Cuzick model does.  相似文献   

6.
Amyotrophic lateral sclerosis (ALS) and spinal muscular atrophy (SMA) are progressive fatal neurodegenerative diseases. They differ in their disease development but have in common a loss of motor neuron as they progress. Research is ongoing to further understand the origin of these diseases but this common thread of motor neuron loss has provided a target for the development of therapies for both ALS and SMA. It is the linked fields of gene and cell therapy that are providing some of the most interesting therapeutic possibilities.  相似文献   

7.
Malignant tumors originate from somatic mutations and other genomic and epigenomic alterations, which lead to loss of control of the cellular circuitry. These alterations present patterns of co‐occurrence and mutual exclusivity that can influence prognosis and modify response to drugs, highlighting the need for multitargeted therapies. Studies in this area have generally focused in particular malignancies and considered whole genes instead of specific mutations, ignoring the fact that different alterations in the same gene can have widely different effects. Here, we present a comprehensive analysis of co‐dependencies of individual somatic mutations in the whole spectrum of human tumors. Combining multitesting with conditional and expected mutational probabilities, we have discovered rules governing the codependencies of driver and nondriver mutations. We also uncovered pairs and networks of comutations and exclusions, some of them restricted to certain cancer types and others widespread. These pairs and networks are not only of basic but also of clinical interest, and can be of help in the selection of multitargeted antitumor therapies. In this respect, recurrent driver comutations suggest combinations of drugs that might be effective in the clinical setting, while recurrent exclusions indicate combinations unlikely to be useful.  相似文献   

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Mitochondrial function has long been the focus of many therapeutic strategies for ameliorating age-related neurodegeneration and cognitive decline. Historically, the role of mitochondria in non-neuronal cell types has been overshadowed by neuronal mitochondria, which are responsible for the bulk of oxidative metabolism in the brain. Despite this neuronal bias, mitochondrial function in glial cells, particularly astrocytes, is increasingly recognized to play crucial roles in overall brain metabolism, synaptic transmission, and neuronal protection. Changes in astrocytic mitochondrial function appear to be intimately linked to astrocyte activation/reactivity found in most all age-related neurodegenerative diseases. Here, we address the importance of mitochondrial function to astrocyte signaling and consider how mitochondria could contribute to both the detrimental and protective properties of activated astrocytes. Strategies for protecting astrocytic mitochondrial function, promoting bidirectional transfer of mitochondria between astrocytes and neurons, and transplanting healthy mitochondria to diseased nervous tissue are also discussed.  相似文献   

10.
Malignant osteopetrosis, a severe disease causing early infantile death in humans, is caused by mutations in the TCIRG1, CLCN7, or OSTM1 genes. We have established the molecular basis of malignant osteopetrosis in a Chinese family by means of whole-genome scans based on high-density single-nucleotide polymorphism (SNP) microarrays. Because the parents were consanguineous, the disease-causing locus should be located in an autozygous chromosomal region. Mapping revealed that among the three possible causal loci, only the CLCN7 gene was located in an autozygous region. Mutational analysis of the CLCN7 gene showed that the proband was homozygous for a novel missense mutation, p.I261F. p.I261 is located in helix F of the chloride channel, near a critical site for gating of the channel. This mapping study prepares the ground for future mutation studies by decreasing the burden of completely sequencing all possible loci for this disease. This approach can be used to standardize molecular investigations of genetic diseases due to consanguinity to a whole-genome scan and subsequent sequencing of the mapped disease gene.  相似文献   

11.
This report summarizes the results on 39 patients with Gaucher disease who have been genotyped, evaluated, and/or followed at this center. Mutation analysis for 4 common mutations; N370S, L444P, 84gg and IVS2 (+1), was performed for all patients. Mutation analysis identified both mutant alleles in 69% and at least one mutant allele in 90% of all chromosomes. This study group of 39 patients included 32 type 1, four type 2 and three type 3 patients. We include the details of the clinical course of two patients with Gaucher disease treated with enzyme replacement therapy (ERT). One patient with chronic neuronopathic Gaucher disease has been treated with enzyme replacement therapy (ERT) at a dose of 60 U/kg every 2 weeks since 2.5 years of age and has shown no progression of neurologic involvement. A second patient with non-neuronopathic Gaucher disease has demonstrated an unusually delayed response to ERT. No clinical response was noted following 17 months of treatment at 60 U/kg every 2 weeks. Only after the dose was increased to 60 U/kg every week was a clinical response evident. Response to treatment at 15 U/kg every 2 weeks was variable in the four type 1 patients treated at the lower dose. In two of these patients with identical genotypes, one patient demonstrated a positive clinical response to low dose treatment while the other patient did not.  相似文献   

12.
Drousiotou A, DiMeo I, Mineri R, Georgiou Th, Stylianidou G, Tiranti V. Ethylmalonic encephalopathy: application of improved biochemical and molecular diagnostic approaches. Ethylmalonic encephalopathy (EE, OMIM # 602473) is an autosomal recessive metabolic disorder of infancy affecting the brain, the gastrointestinal tract and peripheral vessels. It is caused by a defect in the ETHE1 gene product, which was recently shown to be part of a metabolic pathway devoted to sulphide detoxification. We report the application of improved biochemical and molecular approaches to the diagnosis of three cases of EE from two unrelated Cypriot families. The children presented all the typical biochemical hallmarks of the disease including elevated lactate and butyrylcarnitine in blood and elevated urinary excretion of ethylmalonic acid, 2‐methylsuccinate, isobutyrylglycine and isovalerylglycine. We also detected an elevated level of thiosulphate in urine, which we propose as an additional biochemical marker of the disease. The proband of the first family was shown to be a compound heterozygote for a missense mutation in exon 5, L185R, and a deletion of exon 4. The deletion was identified using quantitative real‐time polymerase chain reaction (qRT‐PCR). Using the same technique, the proband of the second family was found to be homozygous for the exon 4 deletion. A prenatal diagnosis was performed for the second family using qRT‐PCR, thus establishing the usefulness of RT‐PCR in prenatal diagnosis.  相似文献   

13.
Autoimmune diseases are characterized by the recognition of self-antigens by the immune system, which leads to inflammation and tissue damage. B cells are directly and indirectly involved in the pathophysiology of autoimmunity, both via antigen-presentation to T cells and production of proinflammatory cytokines and/or autoantibodies. Consequently, B lineage cells have been identified as therapeutic targets in autoimmune diseases. B cell depleting strategies have proven beneficial in the treatment of rheumatoid arthritis (RA), systemic lupus erythematous (SLE), ANCA-associated vasculitis (AAV), multiple sclerosis (MS), and a wide range of other immune-mediated inflammatory diseases (IMIDs). However, not all patients respond to treatment or may not reach (drug-free) remission. Moreover, B cell depleting therapies do not always target all B cell subsets, such as short-lived and long-lived plasma cells. These cells play an active role in autoimmunity and in certain diseases their depletion would be beneficial to achieve disease remission. In the current review article, we provide an overview of novel strategies to target B lineage cells in autoimmune diseases, with the focus on rheumatic diseases. Both advanced therapies that have recently become available and more experimental treatments that may reach the clinic in the near future are discussed.  相似文献   

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This study presents the first molecular data on the basis and the origin of Huntington disease in Croatia and is the first such analysis performed among a Slavic population. We analyzed three trinucleotide polymorphisms in the HD gene: CAG, CCG and GAG Δ2642 (E2642del) triplets. Analysis of the CAG repeat size among 44 Huntington patients (39‐66 CAGs) and 51 normal individuals (9‐34 CAGs) showed that the range of the repeats was similar to previous findings. The frequency of the CCG and Δ2642 polymorphic alleles on N and HD chromosomes was found to correlate well with earlier reports for Western European populations. We found significance for both the CCG7 allele (p=0.004) and the Δ2642 allele (p<0.001) among HD chromosomes. The CCG7 allele was overpresented among affected chromosomes (94.6%), but was also the most frequent CCG allele among normal chromosomes (66.7%). Interestingly, the Δ2642 allele was present on 40.5% HD chromosomes compared to only 9.8% of control chromosomes. Our results indicate that HD mutations in Croatia could be of the same origin as in Western populations and also support the multi‐step hypothesis for generating new HD alleles. Similar frequencies and distributions of both the CCG and the Δ2642 polymorphisms in Croatia and Western European normal chromosomes indicate that the prevalence rate of HD in Croatia may be as high as in Western populations. Since we estimated a lower prevalence rate (1 : 100,000), we assume that there are still many misdiagnosed and/or unrecognized cases of Huntington disease in Croatia. © 2002 Wiley‐Liss, Inc.  相似文献   

16.
PurposeThis study aimed to systematically review and summarize gene therapy treatment for monogenic retinal and optic nerve diseases.MethodsThis review was prospectively registered (CRD42021229812). A comprehensive literature search was performed in Ovid MEDLINE, Ovid Embase, Cochrane Central, and clinical trial registries (February 2021). Clinical studies describing DNA-based gene therapy treatments for monogenic posterior ocular diseases were eligible for inclusion. Risk of bias evaluation was performed. Data synthesis was undertaken applying Synthesis Without Meta-analysis guidelines.ResultsThis study identified 47 full-text publications, 50 conference abstracts, and 54 clinical trial registry entries describing DNA-based ocular gene therapy treatments for 16 different genetic variants. Study summaries and visual representations of safety and efficacy outcomes are presented for 20 unique full-text publications in RPE65-mediated retinal dystrophies, choroideremia, Leber hereditary optic neuropathy, rod-cone dystrophy, achromatopsia, and X-linked retinoschisis. The most common adverse events were related to lid/ocular surface/cornea abnormalities in subretinal gene therapy trials and anterior uveitis in intravitreal gene therapy trials.ConclusionThere is a high degree of variability in ocular monogenic gene therapy trials with respect to study design, statistical methodology, and reporting of safety and efficacy outcomes. This review improves the accessibility and transparency in interpreting gene therapy trials to date.  相似文献   

17.
Wilson disease (WND) is caused by a deficiency of the copper-transporting enzyme, P-type ATPase (ATP7B). Twelve different mutations have previously been identified in Taiwan Chinese with Wilson disease. We, herein, report another 4 missense mutations, 1 of which is novel. We did haplotype analysis of Taiwanese WND chromosomes, using three well characterized short tandem repeat markers (haplotype was assigned in the order of D13S314-D13S301-D13S316). Association correlation was found between the mutations and their respective haplotypes. Haplotype-deduced pedigree analysis was shown to be helpful in the mutation analysis of WND chromosomes and in the molecular assessment of both pre-symptomatic WND patients and carriers. Given the complexity and heterogeneity of the mutation spectrum of ATP7B, we suggest that haplotype analysis should be performed before full-scale mutation analysis. Received: April 21, 2000 / Accepted: June 2, 2000  相似文献   

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Research on alkaptonuria (AKU; OMIM # 230500) in Slovakia started in 1968 by the Research Laboratory (later on the Institute) for Clinical Genetics at Martin. Its first stage was focused on clinical, biochemical, genetic and epidemiologic questions and on the reasons for the high prevalence of AKU in Slovakia. Based on a screening programme of now over 611,000 inhabitants (509,000 newborns) the world-wide highest incidence of AKU (1 in 19,000) was recorded, and a total of 208 patients (110 children) were registered. Extensive genealogical studies (sometimes over two centuries) resulted in the fusion of several "unrelated" nuclear families into larger pedigrees and enabled tracing most AKU ancestors to their original geographic localities, predominantly in remote mountain areas. A likely founder effect was detected among the shepherd population of the so-called Valachian colonization that resulted in a high degree of inbreeding and persisting genetic isolation. These epidemiologic data formed the basis for molecular studies in collaboration with the Würzburg group. The AKU locus was mapped to human chromosome 3q2 by orthology to the mouse locus aku. Following the cloning of the homogentisate-1,2 dioxygenase (HGD) genes from human and mouse, nine different mutations were identified in 21 AKU index patients. These include 4 missense, 2 splice-site, 2 single-base insertion and 1 deletion mutation. The most frequent mutations among the 42 AKU chromosomes of the index cases are c.648G > A (Gly161Arg; 42.9%), and c.1278insC (Pro370fs; 19.1%). To date, the genotypes of 29 patients and of 74 gene carriers from 21 families have been established. The highest prevalence and allelic heterogeneity were observed in the Kysuce district with five different mutations. Molecular epidemiology studies by haplotyping were carried out to uncover the original geographic localities of all AKU index chromosomes. This strongly suggests that several founders have contributed to the HGD gene mutation pool. While there is no straightforward explanation for the clustering of independent mutations, the genetic isolation in the past is likely to be responsible for the high prevalence of AKU in Slovakia.  相似文献   

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