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61.
应用创造酶切位点PCR-RFLP检测乙醇脱氢酶2基因多态性   总被引:3,自引:1,他引:2  
目的建立简便易行经济适用的乙醇脱氢酶2(ADH2)基因单核苷酸多态性检测方法。方法根据单碱基突变位点的碱基替代情况设计引物,其中一条引物根据突变位点邻近序列设计,人为引入错配碱基,使引物3′端和单碱基突变的一种突变型在PCR扩增后形成一个酶切位点,并应用相应内切酶进行酶切鉴定,通过PCR-RFLP技术判断ADH2基因SNP位点多态性。结果设计一对特异引物并PCR扩增含ADH2多态位点的DNA片段,使用限制性内切酶Bsh1236I酶切判断ADH2位点多态性,PCR和酶切效果均较好。结论应用创造酶切位点PCR-RFLP原理建立的ADH2多态位点检测方法具备简便、经济、快速的特点。  相似文献   
62.
目的 对新疆哈萨克及维吾尔族人群中系统性红斑狼疮(SLE)及类风湿关节炎(RA)患者甘露糖结合凝集素基因54位密码子点突变进行测定并分析.方法 PCR-RFLP.结果 42例哈萨克族SLE患者基因频率:0.536(GGC),0.464(GAC);24例维吾尔族SLE患者基因频率:0.667(GGC),0.333(GAC);22例哈萨克族RA患者基因频率:0.614(GGC),0.386(GAC);15例维吾尔族RA患者基因频率:0.733(GGC),0.267(GAC).结论 MBL不同的基因型和这些疾病发生可能存在相关.  相似文献   
63.
Increasing numbers of single-nucleotide substitutions of the human flavin-containing monooxygenase 3 (FMO3) gene are being recorded in mega-databases. Phenotype–gene analyses revealed impaired FMO3 variants associated with the metabolic disorder trimethylaminuria. Here, a series of reliable FMO3 genotyping confirmation methods was assembled and developed for 45 impaired FMO3 variants, mainly found in Japanese populations, using singleplex or duplex polymerase chain reaction (PCR)–restriction fragment length polymorphism (RFLP) methods and singleplex, duplex, or tetraplex allele-specific PCR methods. Nine PCR-RFLP procedures with single restriction enzymes and fourteen duplex PCR-RFLP procedures (for p.Trp41Ter and p.Thr329Ala, p.Met66Val and p.Leu163Pro, p.Pro70Leu and p.Glu308Gly, p.Asn114Ser and p.Ser195Leu, p.Glu158Lys and p.Ile441Thr, p.Cys197Ter and p.Trp388Ter, p.Arg205Cys and p.Val257Met, p.Arg205His and p.Cys397Ser, p.Met211ArgfsTer10 and p.Arg492Trp, p.Arg223Gln and p.Leu473Pro, p.Met260Val and p.Thr488Ala, p.Tyr269His and p.Ala311Pro, p.Ser310Leu and p.Gly376Glu, and p.Gln470Ter and p.Arg500Ter) were newly established along with eight singleplex (for p.Pro153GlnfsTer14, p.Gly191Cys, p.Pro248Thr, p.Ile486Met, and p.Pro496Ser, among others), one duplex (p.Ile199Ser and p.Asp286Tyr), and one tetraplex (p.Ile7Thr, p.Val58Ile, p.Thr201Lys, and p.Gly421Val) allele-specific PCR systems. This series of systems should facilitate the easy detection in a clinical setting of FMO3 variants in Japanese subjects susceptible to low drug clearances or drug reactions possibly caused by impaired FMO3 function.  相似文献   
64.
Various molecular methods have been used for the rapid identification of mycobacterial species. In this survey, evaluation of antibiotic resistance and PCR-restriction fragment length polymorphism analysis (PRA) of the hsp65 gene was carried out for identification of non-tuberculosis mycobacteria (NTM) isolates from different clinical specimens. Forty-eight different mycobacterial isolates were selected and followed by the conventional and PRA of hsp65 for species identification. The antibiotic susceptibility test was carried out according to standard methods. A 439 bp PCR product of hsp65 in all selected isolates was amplified and digested with the BstEII and HaeIII restriction enzymes. The restriction fragment length polymorphism (RFLP) patterns were analyzed for species identification. Using PRA for 48 mycobacterial selected isolates, including 15 M. tuberculosis, one M. bovis and all 32 isolates of NTM, revealed 11 different species among the NTM isolates. The most frequent NTM isolates were M. kansasii, M. gordonae III, M. marinum, M. chelonae, M. scrofluaceum and M. gastri. In most cases, the PRA results were perfectly in accordance with the classical biochemical method. Combination of resistance to rifampin and isoniazid was present among M. kansasi, M. gordoniae III, M. scrofluaceum, M. chelonae, M. marinum, M. gastri, M. gordoniae II and M. trivale isolates. A high incidence of co-resistance to six, five, four and three anti-TB drugs was observed in 18.5%, 9.1%, 6.6% and 11.7% of all NTM isolates, respectively. Our results showed that PRA, in comparison with classical methods, is rapid and accurate enough for the identification of mycobacterial species from LJ medium. Additionally, we found that in Iran we have a highly diverse population of NTM isolates among patients suspected of having TB.  相似文献   
65.
Study on Genetic Diagnosis of Spinal Muscular Atrophy   总被引:1,自引:0,他引:1  
IntroductionChildhood-onsetspinalmuscularatrophy(SMA)isanautosomalrecessivedisease,afect-ing1/6000birthsinnorthAmericanandEur...  相似文献   
66.
Locus HLA-DRB3 codes for the serologically defined supertypic specificity DRw52 in HLA-DR3, -5 and -w6 haplotypes. Three specificities of DRw52 (DRw52a, -b and -c) can further be distinguished by cellular techniques or by DNA typing with allele-specific oligonucleotide probes. These specificities were recently reported to have significant importance in antigen presentation. To avoid a time-consuming hybridization procedure, we have developed a simple typing system using PCR and subsequent digestion by allele-specific restriction endonucleases. A system was established with locus-specific amplification of HLA-DRB3 and digestion by the enzymes KpnI, ScaI and HinfI which recognize unique restriction sites within the amplified region. This allowed HLA-DRB3 typing on agarose gel by determining whether the amplification product has been digested or not. This typing system was compared to conventional oligotyping by analyzing 145 RFLP-typed individuals for their DRw52 specificity using both methods. Agarose typing correlated well with oligotyping and was shown to be more simple and practical even in heterozygous individuals.  相似文献   
67.
胰腺癌组织K-ras基因点突变检测的临床意义   总被引:1,自引:0,他引:1  
目的 :探讨胰腺癌中K -ras 12密码子点突变对胰腺癌诊断的价值。方法 :采用聚合酶链反应 -限制性片段长度多态性分析 (PCR -RFLP)检测了 2 3例胰腺癌K -ras基因第 12密码子点突变 ,并评价其临床应用价值。结果 :2 3例胰腺癌组织标本中K -ras基因突变率为 78.3 % (18/ 2 3 ) ,胰腺癌K -ras基因突变与胰腺癌分级、临床分期及伴随局部淋巴结转移无显著相关 (P >0 .0 5 )。结论 :胰腺癌中K -ras 12密码子突变率高 ,特异性强 ,有助于胰腺癌的诊断  相似文献   
68.
Rheumatoid arthritis (RA) is a common autoimmune disease with a complex genetic background. The peptidyl arginine deiminase type IV (PADI4) gene has been associated with RA susceptibility in several populations. We addressed the relationship between three exonic PADI4 gene single nucleotide polymorphisms (SNPs) PADI4_89 (rs11203366), PADI4_90 (rs11203367) and PADI4_92 (rs874881) and related haplotypes with RA in a population from Southern México. This study included 200 RA patients and 200 control subjects. The SNPs were evaluated using the polymerase chain reaction-restriction fragment-length polymorphism (PCR-RFLP) technique, and antibodies to cyclic citrullinated peptides (anti-CCP) were measured by enzyme-linked immunosorbent assay (ELISA). In this population, the minor alleles of PADI4_891G, PADI4_901T and PADI4_921G gene polymorphisms were associated with RA susceptibility (OR = 1.34, p = 0.04; OR = 1.35, p = 0.03; OR = 1.34, p = 0.04; respectively). The GTG haplotype was also significantly associated with RA (OR = 2.27 95%CI = 1.18–4.41; p = 0.008), but did not show association with levels of anti-CCP antibodies and clinical parameters. In conclusion, our replication study in a Southern Mexican population suggests that PADI4 individual polymorphisms and the related susceptibility haplotype (GTG) are also genetic risk markers for RA.  相似文献   
69.

Background

Due to the lack of a suitable and economic test for the analysis of the polymorphism at codon 167, we developed a new PCR-RFLP technique, based on a modified forward primer (UT-HC167 MF-primer), to identify simultaneously the SNPs at codons 167 and 200 of isotype 1 β-tubulin gene of Haemonchus contortus.

Methods

There already are several safe and easy methods for identification of point mutations at codons 198 and 200. Due to the lack of a reliable and easy method for the detection of the single nucleotide polymorphism (SNP) at codon 167, we developed an innovative PCR-RFLP technique based on a modified forward primer (UT-HC167 MF-primer), in which the nucleotide T at the position 443 was substituted through a nucleotide A creating a restriction site for restriction endonuclease SnaB I in the nucleotide sequences including codon 167. A total of 138 adult male H. contortus were collected from three different geo-climatic areas of Iran. The isolated genomic DNA of each single worm was amplified by PCR using primers flanking codon 167. The PCR product (527 bp) was then amplified by semi-nested PCR using the UT-HC167 MF-primer and the reverse primer achieving a PCR product of 451 bp in length. This PCR product was subsequently digested with the restriction endonucleases SnaB I and TaaI for analysis of the mutations at codons 167 and 200, respectively.

Results

All worms had two alleles encoding for phenylalanine (BZss homozygote) for both codons.

Conclusion

Using the UT-HC167 MF-primer and a suitable reverse primer designed upstream from codon 200, it is possible to amplify a PCR product which can be used for analysis of the SNPs at all three mentioned codons using RFLP.  相似文献   
70.
目的用PCR-RFLP方法对rDNA-ITS1片段进行分析,以进一步明确云贵地区是否存在牛带绦虫亚洲亚种,并建立一种快速鉴定方法. 方法 取贵州都匀株(DY)、贵州从江株(CJ)、云南大理株(DL)带绦虫及台湾株(TW)成虫标本,剪取孕节,抽提DNA,PCR扩增rDNA- ITS1片段,分别用4种限制性内切酶MspI、CfoI、AluI、RsaI对扩增片段作酶切分析. 结果 PCR产物经AluI、RsaI酶切后, TW、DL、DY和CJ株RFLP图谱一致;经MspI、CfoI酶切后,TW、DL和DY株RFLP图谱一致,CJ株显著不同. 结论 1)DL和DY株与TW株同属牛带绦虫亚洲亚种;而CJ株是传统牛带绦虫;2)rDNA-ITS1的PCR-RFLP分析方法简便,可以用于带绦虫的分类学研究.  相似文献   
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