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71.
72.
胃癌高系家族成员胃蛋白酶原C基因多态性及其诊断意义的探讨 总被引:1,自引:0,他引:1
采用限制性酶切片段长度多态性分析法,检测在胃癌高发区庄河检出的19例胃癌高系家族成员胃蛋白酶原C基因多态性,发现三种常见片段及一种稀有片段。对其中4例携带稀有片段的受检者进行了胃镜追踪观察,2.5年后发现1例早期胃癌。本文对此作了初步探讨。 相似文献
73.
SNP及其在畜牧业中的应用前景 总被引:4,自引:0,他引:4
张利平 《国外畜牧学(草食家畜)》2003,(3):30-32
SNP(single nucleotide polymorphisns-单核苷酸多态性)是继限制性片段长度多态性和微卫星之后,新发展起来的第3代分子标记。已成为一类新的遗传标记,广泛应用于基因定位、克隆和遗传多样性研究。本文介绍了SNP的特性、检测方法及其在畜牧业研究生产中的广泛利用前景。并提出了SNP研究中遇到的一些问题。 相似文献
74.
L. Cheng †‡ T. Enomoto§ T. Hirota† M. Shimizu † N. Takahashi† M. Akahoshi† A. Matsuda† Y. Dake§ S. Doi¶ K. Enomoto A. Yamasaki S. Fukuda X.-Q. Mao J. M. Hopkin M. Tamari† T. Shirakawa † 《Clinical and experimental allergy》2004,34(8):1192-1201
BACKGROUND: A recent report provided evidence that a disintegrin and metalloprotease domain 33 (ADAM33), a member of the ADAM family, is a novel susceptibility gene in asthma linked to bronchial hyper-responsiveness. However, there has been no investigation of the genetic role of ADAM33 variants in nasal allergy. OBJECTIVE: The purpose of this study was to test the association between ADAM33 polymorphisms and Japanese cedar pollinosis (JCPsis), a most common seasonal allergic rhinitis in Japan. METHODS: We conducted a case-control association study among a Japanese population, involving 95 adult individuals with JCPsis and 95 normal healthy controls. A total of 22 single-nucleotide polymorphisms (SNPs) in ADAM33 were genotyped using PCR-based molecular methods. RESULTS: Six SNPs of ADAM33 gene, three in introns (7575G/A, 9073G/A and 12540C/T) and three in the coding region (10918G/C, 12433T/C and 12462C/T), were strongly associated with JCPsis (P = 0.0002-0.022 for absolute allele frequencies) and most of the SNPs were in linkage disequilibrium with each other. A higher frequency of the common alleles of these SNPs was noted for the subjects with JCPsis in comparison with healthy controls. We also identified a haplotype associated with the disease susceptibility. In addition, associations were found between ADAM33 polymorphisms and various cedar pollinosis phenotypes including clinical severity, eosinophil counts in nasal secretion and allergen-specific IgE levels in sera, but not total serum IgE levels. CONCLUSION: These results indicate that polymorphisms in the ADAM33 gene are associated with susceptibility to allergic rhinitis due to Japanese cedar pollen, but the functional relationship still needs clarification. 相似文献
75.
T. Iwanaga †‡ A. McEuen† A. F. Walls† J. B. Clough† T. P. Keith§ S. Rorke† S. J. Barton† S. T. Holgate† J. W. Holloway † 《Clinical and experimental allergy》2004,34(7):1037-1042
BACKGROUND: Mast cell chymase has the potential to be an important mediator of inflammation and remodelling in the asthmatic lung. Previous studies have examined association between promoter polymorphism of the chymase gene (CMA1) and allergic phenotypes but the significance of this polymorphism is unclear. We have examined association of a CMA1 variant in relation to asthma in a large UK Caucasian family cohort. METHODS: A polymorphism of the CMA1 gene promoter (-1903G/A) was genotyped in 341 asthmatic families and in 184 non-asthmatic adults recruited from the UK PCR-RFLP based genotyping. Association with asthma diagnosis, atopy, specific and total IgE, and atopy and asthma severity was examined. RESULTS: Case-control studies did not reveal a significant difference in allele frequency between asthmatics and controls. A significant association was found between CMA1 genotypes and total IgE levels in subjects with self-reported eczema that remained significant after correction for multiple testing (median total serum IgE GG 297 kU/L, GA 144 kU/L, AA 48.4 kU/L, Pc=0.0032). CONCLUSION: These data suggest that CMA1 promoter polymorphism does not contribute to asthma susceptibility or severity but may be involved in regulating IgE levels in patients with eczema. 相似文献
76.
Characterization of a functional promoter polymorphism of the human tryptophan hydroxylase 2 gene in serotonergic raphe neurons. 总被引:2,自引:0,他引:2
77.
S. Doğru-Abbasoğlu G. Aykaç-Toker H. A. Hanagasi H. Gürvit M. Emre M. Uysal 《Neurological sciences》2007,28(1):31-34
Abstract Alzheimer's disease (AD) is defined pathologically by the presence of β-amyloid plaques, neurofibrillary tangles and extensive
neuronal loss. Evidence indicates that increased DNA damage may contribute to neuronal loss in AD. Recently, it has been shown
that in AD neurons have a reduced capacity for some types of DNA repair. Polymorphisms in DNA repair genes may be associated
with differences in repair efficiency of DNA damage. Variants of several DNA repair genes, including the base excision repair
gene XRCC1, have been described previously. We hypothesised that Arg194Trp polymorphism of XRCC1 gene may contribute to genetic susceptibility for AD. In order to test this hypothesis, we investigated
Arg194Trp polymorphism at the XRCC1 gene in the DNA samples of 98 patients with AD and 95 healthy subjects. The frequency of the Trp allele was more pronounced among cases (11.2%) compared with controls (5.8%). On combining the homozygous and heterozygous
variants of each codon, the variants seemed to be at twofold risk of AD, although the risk estimates were not statistically
significant (OR=1.95, 95% CI 0.88–4.34, p=0.09). In addition, the 194Trp allele revealed a borderline significance (OR=2.05, 95% CI 0.96–4.37, p=0.056). According to our results, it may be speculated that the polymorphic variants of XRCC1 codon 194 have a role in the
development of AD. 相似文献
78.
Objective: To develop a new method for the detection of TPMT gene mutations and determine the frequencies of four TPMT alleles, TPMT^*1,^*3A,^*3B and ^*3C in a healthy Chinese population. Methods:A TDI-FP assay system was set up in out lab. To evaluate this system, 220 healthy individuals were analyzed for the polymorphic sites at positions 460 (G→A)and 719 (A→G)of the TPMP gene using our new TDI FP method. Results:Three TPMP *3C(G^460→G^719) heterozygotes were identified, TPMP ^*3A and TPMP ^*3B were not found. All mutations were confirmed by conventional DNA sequencing analysis. Conclusion:TDI-FP method has proven to be very efficient as a rapid and accurate approach for TPMP genotyping. TPMP ^*3C was the only polymorphism identified in this clinical samples we have registered. 相似文献
79.
目的 研究苏州地区汉族人血小板糖蛋白Ⅲa基因TaqⅠ多态性与脑梗死发生的相关性。 方法 应用PCR技术结合TaqⅠ酶切分析、聚丙烯酰胺凝胶电泳 ,研究了苏州地区汉族正常人与脑梗死患者血小板糖蛋白Ⅲa基因TaqⅠ多态性特点。 结果 正常对照组TaqⅠ等位基因的频率分别为C 5 3.8%、A 4 6 .2 %。脑梗死组TaqⅠ等位基因频率分别为C 5 0 .6 %、A 4 9.4 %。脑梗死组和对照组之间无显著性差异 (P >0 .0 5 )。结论 苏州地区汉族人血小板糖蛋白Ⅲa基因TaqⅠ多态性与脑梗死发生无关。 相似文献
80.
白细胞介素-6基因启动子多态性与子宫内膜异位症的相关性分析 总被引:1,自引:0,他引:1
目的 研究白细胞介素-6(IL-6)基因启动子-174G/C、-572C/G及-597G/A的多态性在子宫内膜异位症(EM)患者及非EM育龄女性(对照组)中的分布.方法 采用病例对照研究的方法 ,选取98例EM患者,其中轻、中、重型(即Ⅱ、Ⅲ、Ⅳ期)分别为22、35、41例,以99名非EM育龄女性外周血白细胞为对照,应用聚合酶链反应-限制性片段长度多态性技术检测IL-6基因启动子-174、-572及-597的多态性,比较两组IL-6启动子基因型和等位基因的分布频率,对两组间基因多态性存在明显差异的基因位点进行组间比较.结果 IL-6基因启动子-174位点的GG、CG和CC基因型在EM组中分别为100%、0%、0%,在对照组中分别为98.99%、1.01%、0%,两组的分布频率差异无显著性;-572位点的CC、CG和GG基因型在EM组中分别为55.10%、42.86%、2.04%,在对照组中分别为70.71%、28.28%、1.01%,两组的基因分布频率差异有显著性;所有实验对象-597位点的基因型均为GG型,两组均无GA及AA基因型存在;-572位点的CC、CG和GG基因型在轻型EM组中分别为59.09%、40.90%、0%,在中型EM组中分别为54.29%、42.86%、2.85%,在重型EM组中分别为53.66%、43.90%、2.44%,轻、中、重组间基因型及等位基因分布频率无明显差异.结论 IL-6基因启动子的-174位点变异率极低,-597位点末发现变异,以上两位点基因变异与EM的发病无明显相关性;而启动子-572位点的多态性分布与EM的发病具有一定程度的相关性,但与疾病的严重程度无关. 相似文献