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Mutation System (mutation + system)
Kinds of Mutation System Selected AbstractsA review of current large-scale mouse knockout effortsGENESIS: THE JOURNAL OF GENETICS AND DEVELOPMENT, Issue 2 2010Chunmei Guan Abstract After the successful completion of the human genome project (HGP), biological research in the postgenome era urgently needs an efficient approach for functional analysis of genes. Utilization of knockout mouse models has been powerful for elucidating the function of genes as well as finding new therapeutic interventions for human diseases. Gene trapping and gene targeting are two independent techniques for making knockout mice from embryonic stem (ES) cells. Gene trapping is high-throughput, random, and sequence-tagged while gene targeting enables the knockout of specific genes. It has been about 20 years since the first gene targeting and gene trapping mice were generated. In recent years, new tools have emerged for both gene targeting and gene trapping, and organizations have been formed to knock out genes in the mouse genome using either of the two methods. The knockout mouse project (KOMP) and the international gene trap consortium (IGTC) were initiated to create convenient resources for scientific research worldwide and knock out all the mouse genes. Organizers of KOMP regard it as important as the HGP. Gene targeting methods have changed from conventional gene targeting to high-throughput conditional gene targeting. The combined advantages of trapping and targeting elements are improving the gene trapping spectrum and gene targeting efficiency. As a newly-developed insertional mutation system, transposons have some advantages over retrovirus in trapping genes. Emergence of the international knockout mouse consortium (IKMP) is the beginning of a global collaboration to systematically knock out all the genes in the mouse genome for functional genomic research. genesis 48:73,85, 2010. © 2010 Wiley-Liss, Inc. [source] HSP70-hom gene single nucleotide (+2763 G/A and +2437 C/T) polymorphisms in sarcoidosisINTERNATIONAL JOURNAL OF IMMUNOGENETICS, Issue 2 2006K. Bogunia-Kubik Summary In the present study, two coding polymorphisms within the heat shock protein 70-hom gene (HSP70-hom) were analysed. One hundred and thirty-eight individuals were studied, including 42 Polish patients with sarcoidosis, 13 of which presented with Löfgren's syndrome (LS), and 94 control subjects. Dimorphisms at positions +2763 (A/G) and +2437 (C/T) of the HSP70-hom gene were typed using amplification refractory mutation system and polymerase chain reaction,restriction fragment length polymorphism technique, respectively. A significant prevalence of the HSP(+2437)-C allele and the HSP(+2437)-CC homozygous genotype was observed in patients with sarcoidosis and in those presenting with LS as compared to controls (P < 0.001 in all comparisons made). A majority of HLA-DRB1*03-positive patients with LS were carrying both HSP(+2437)-C and (+2763)-G alleles, and the concomitant presence of these three genetic factors was more frequent among patients with LS as compared to patients without LS (0.54 vs. 0.17, P < 0.05) and controls (0.54 vs. 0.01, P < 0.001). The association of the HSP(+2437)-C allele with sarcoidosis and LS appeared to be independent of the presence of DRB1*03, although this HLA specificity was associated with LS manifestation. The HSP(+2763)-G allele was independently associated with neither sarcoidosis nor LS. However, this HSP(+2763)-G allele was present with either DRB1*03 or HSP(+2437)-C within the same haplotypes in the patients and this might explain the observed prevalence of DRB1*03, HSP(+2437)-C and (+2763)-G in patients with LS. In conclusion, HSP(+2437)-C allele was found as a factor associating with susceptibility to sarcoidosis and LS. [source] Elevated serum level and gene polymorphisms of TGF-,1 in gastric cancerJOURNAL OF CLINICAL LABORATORY ANALYSIS, Issue 3 2008Xue Li Abstract Transforming growth factor (TGF)-,1, as a candidate tumor marker, is currently of interest. In this study, serum TGF-,1 levels in gastric cancer (GC) patients and healthy volunteers were measured using enzyme-linked immunosorbent assay (ELISA). In addition, single nucleotide polymorphisms (SNPs) of the TGF-,1 gene at codon 10 and codon 25 were identified by means of amplification refractory mutation system,polymerase chain reaction (ARMS-PCR) and sequence analysis. Our results indicated that serum concentrations of TGF-,1 in GC patients were significantly higher than those in the control, and positively correlated with tumor mass, invasion, metastasis, and clinical stage. The serum TGF-,1 levels of patients recovering from radical resection were markedly lower than those before surgery. Meanwhile, no deoxyribonucleic acid (DNA) sequence variation at codon 25 of the TGF-,1 gene was found and a TGF-,1 gene polymorphism at codon 10 did not show obvious correlations with either TGF-,1 expression or clinicopathological parameters of GC. Our evidence suggested that serum concentration of TGF-,1 might be a novel tumor marker for GC and the polymorphisms of TGF-,1 gene did not play a role as a determinant of serum TGF-,1 concentration or as a genetic risk factor in the gastric carcinogenesis and progression. J. Clin. Lab. Anal. 22:164,171, 2008. © 2008 Wiley-Liss, Inc. [source] CTLA4 exon 1 and promoter polymorphisms in patients with multiple sclerosisACTA NEUROLOGICA SCANDINAVICA, Issue 6 2009G. Yousefipour Objective ,, The polymorphisms of exon 1 (+49 A/G) and promoter regions (,1722 T/C, ,1661 A/G and ,318 C/T)of cytotoxic T lymphocyte antigen 4 (CTLA4) and also haplotypes constructed from mentioned loci were investigated amongst 153 Iranian patients with definite multiple sclerosis (MS) and 190 healthy controls. Methods ,, The polymorphisms were genotyped by PCR-restriction fragment length polymorphisms and PCR-amplification refractory mutation system. The 4-locus haplotypes were estimated by Arlequin software (University of Berne, Berne, Switzerland). Results ,, Preliminary results showed significant increase of +49 G allele and ,1661 AG genotype, as well as TGCA haplotype among patients than controls (P < 0.036, P = 0.009 and P < 0.010, respectively). The distribution of ,1722 T/C, ,1661 A/G, ,318 C/T and +49 A/G (TACA) haplotype, from the contrary, was observed to be significantly increased among controls (P < 0.001). Conclusions ,, After Bonferroni correction, the results provide preliminary evidence that CTLA4 genetic variation at ,1661 locus may render Iranian individuals to be more susceptible to MS, whereas harboring TACA haplotype might be protective. [source] Distribution of HLA-A, B alleles and polymorphisms of TAP and LMP genes in Korean patients with atopic dermatitisCLINICAL & EXPERIMENTAL ALLERGY, Issue 12 2001H. J. Lee Background Atopic dermatitis has been seen to result from multifactorial inheritance, with interaction between genetic and environmental factors. The genetic association may differ according to the ethnic backgrounds. Objective The purpose of this study was to investigate the genetic factors in Korean atopic dermatitis patients by studying the human leucocyte antigen (HLA) class I association and polymorphisms of transporters associated with antigen presentation (TAP) and low-molecular-weight polypeptide (LMP) genes. Methods HLA-A and B genotyping was performed in 53 atopic dermatitis patients and 184 healthy controls using the standard microlymphocytotoxicity technique. TAP1, TAP2, LMP2, and LMP7 gene polymorphisms were anaylzed using the polymerase chain reaction (PCR)-single strand conformation polymorphism (SSCP), PCR-amplification refractory mutation system (ARMS), and PCR-restriction fragment length polymorphism (RFLP). Results Allele frequency of HLA-A24 was significantly increased in patients with atopic dermatitis compared to controls (P < 0.05). HLA-B alleles showed no differences in distribution between patients and controls. Genotype, phenotype, and allele frequencies of TAP1 gene also revealed no differences in distribution between patients and controls. Analysis of TAP2 gene polymorphisms showed increased frequencies of the TAP2*C allele and TAP2*A/TAP2*C genotype in atopic dermatitis patients compared to controls (P < 0.05). Distribution of LMP2 and LMP7 gene polymorphisms was similar for patients and controls. Conclusion This study demonstrates an association of atopic dermatitis with HLA-A24 and TAP2*C alleles in Korean patients. Discrepancy with the previous reports might be related to different patient characteristics and ethnic variations. [source] Multiplex ARMS analysis to detect 13 common mutations in familial hypercholesterolaemiaCLINICAL GENETICS, Issue 6 2007A Taylor DNA analysis and mutation identification is useful for the diagnosis of familial hypercholesterolaemia (FH), particularly in the young and in other situations where clinical diagnosis may be difficult, and enables unambiguous identification of at-risk relatives. Mutation screening of the whole of the three FH-causing genes is costly and time consuming. We have tested the specificity and sensitivity of a recently developed multiplex amplification refractory mutation system assay of 11 low-density lipoprotein receptor gene (LDLR) mutations, one APOB (p.R3527Q) and one PCSK9 (p.D374Y) mutation in 400 patients attending 10 UK lipid clinics. The kit detected a mutation in 54 (14%) patients, and a complete screen of the LDLR gene using single-stranded conformation polymorphism/denaturing high performance liquid chromatography identified 59 different mutations (11 novel) in an additional 87 patients, for an overall detection rate of 35%. The kit correctly identified 38% of all detected mutations by the full screen, with no false-positive or false-negative results. In the patients with a clinical diagnosis of definite FH, the overall detection rate was higher (54/110 = 49%), with the kit detecting 52% of the full-screen mutations. Results can be obtained within a week of sample receipt, and the high detection rate and good specificity make this a useful initial DNA diagnostic test for UK patients. [source] | |||||||||||||