CYP1A1基因Ile-Val和Msp1位点多态性与结直肠癌易感性研究

目的探讨细胞色素P450(CYP1A1)基因异亮氨酸(Ile)-缬氨酸(Val)位点和Msp1位点多态性和结直肠癌的相关关系.方法以病例对照的研究方法,采用PCR-RFLP和AS-PCR技术检测79例结直肠癌和110例对照者的CYP1A1基因Ile-val位点和Msp1位点多态性.结果 Ile-Va三种多态基因型在结直肠癌组和对照组分布差异有显著性(P<0.05),Ile/Val,Val/Val基因型在结直肠癌组的分布频率明显高于对照组;Ile/Val,Val/Val基因型患结直肠癌的危险分别是Ile/Ile基因型的2.113倍和4.203倍;当按吸烟分层后(将Ile/Val,Val/Val基因型合并分析),吸烟组中Ile/Val、Val/Val合并基因型患结直肠癌的危险是Ile/Ile基因型的2.98倍(P<0.05);Msp1位点多态性在结直肠癌和对照组差异无统计学意义.结论 CYP1A1第7外显子的Ile/Val,Val/Val基因型与结直肠癌的易感性有关,突变基因型增加了结直肠癌的患病风险;尚不能认为Msp1多态性与结直肠癌的易感性有关.     

人类MMP3基因2号外显子Lys45Glu单核苷酸多态性与乳腺癌易感性的关系

讨论了基质金属蛋白酶3(MMP3)基因单核苷酸多态性(SNP)与湖北省武汉市人群乳腺癌易感性的关联关系.选择MMP3基因2号外显子Lys45Glu单核苷酸多态性rs679620作为研究对象,采用聚合酶链式反应限制性片段长度多态性分析方法(PCR-RFLP)对195例散发乳腺癌病人和289例正常人群进行了病例-对照分析,运用SHEsis软件和SPSS软件分别计算Hardy-Weinberg数值以及对基因分型数据进行统计分析后表明:MMP3 rs679620(A/G)单核苷酸多态性各个基因型在病例组和对照组分布符合Hardy-Weinberg平衡,A等位基因在病例组中频率(P=0.331)小于对照组(P=0.360),可能为保护因素,但病例和对照的差异不具有统计学意义.在中国武汉地区汉族女性中,MMP3多态性与乳腺癌没有明显关联,但呈现一定的趋势,需加大样本量和增加考察的SNP数量进行深入研究.     

HLA基因多态性与法医学

人类白细胞抗原,简称HLA,基因定位于人类第6号染色体短臂上,是人类最复杂的显形多态遗传系统,基因型可达108之多,在法医学物证鉴定中有着广泛的应用前景,是理想的人类遗传学标记.本文就其基因多态性的研究进展和在法医学中的应用作一综述.     

新疆维吾尔族人TNFβ-804基因多态性与乙型肝炎易感性的相关性研究

目的：研究TNF-β基因单核苷酸多态性（SNP）804位点与新疆地区维吾尔族人乙型肝炎之间的关系。方法：用套式PCR（nested PCR）和等位基因特异性PCR（allele一speciicfic PCR,AS-PCR）法,对120例乙肝患者和120例正常对照者TNF-β基因SNP804多态性位点进行基因分型。结果：SNP804多态性位点C/C基因型和C/A＋AA基因型频率在病例组为77%和23%,正常对照组为88%和12%,两组间基因型和等位基因频率分布差异有显著性（p〈0.05）。结论：TNF-β804多态性位点与新疆维吾尔族人乙肝有明显相关性。     

新疆维吾尔族人TNFβ-804基因多态性与乙型肝炎易感性的相关性研究

目的:研究TNF-β基因单核苷酸多态性(SNP)804位点与新疆地区维吾尔族人乙型肝炎之间的关系。方法:用套式PCR(nested PCR)和等位基因特异性PCR(allele一speciicfic PCR,AS-PCR)法,对120例乙肝患者和120例正常对照者TNF-β基因SNP804多态性位点进行基因分型。结果:SNP804多态性位点C/C基因型和C/A+AA基因型频率在病例组为77%和23%,正常对照组为88%和12%,两组间基因型和等位基因频率分布差异有显著性(p<0.05)。结论:TNF-β804多态性位点与新疆维吾尔族人乙肝有明显相关性。     

新疆汉族食管癌病人ECRG2基因遗传多态性与食管癌易感性关系的研究

为研究食管癌相关基因2（ECRG2）STR多态性与新疆汉族食管癌易感性的关系,在新疆地区进行了一个食管癌研究（食管癌84例,人群对照53例）,采用PCR-SSCP技术检测研究对象的ECRG2 STR基因型.结果显示：ECRG2 STR呈多态性,可分为3种类型：TCA3/TCA3,TCA4/TCA4,TCA3/TCA4,在有转移的食管癌中分布为67.9%、7.1%、25.0%,在无转移的食管癌中分布为14.3%、44.6%、41.1%,两者相比,有显著差异（χ^ 2=26.18,df=2,P＜0.01）.在病例对照研究中,在食管癌中所占比例分别是32.1%、32.1%、35.8%,对照组分别是15.1%、49.1%、35.8%,两组总构成比有显著差异（χ ^2=6.10,P＝0.047）.由此可知ECRG2基因TCA3/TCA3基因型与TCA4/TCA4基因型比较,增加了患食管癌和发生转移的风险.     

MTHFR C677T基因多态性与新疆哈萨克族食管癌易感性关系的研究

为探讨亚甲基四氢叶酸还原酶（MTHFR）基因C677T多态性与哈萨克族食管癌易感性的关系.在食管癌高发区新疆哈萨克族聚居区进行了病例对照研究（食管癌94例,人群对照98例）,采用PCR-RFLP技术检测研究对象的MTHFR基因型.MTHFR C677T呈多态性,可分为3种类型：677CC、677CT、677TT,在食管癌中所占比例分别是56.4%、36.2%、7.4%,对照组分别是58.2%、29.6%、12.2%,两组总构成比无显著差异（χ ^2=1.776,P〉0.05）.因此,MTHFR C677T基因多态性可能与哈萨克族食管癌易感无关.     

ACE基因多态性与异常体液型乳腺癌的易感性

 为探讨血管紧张素转换酶(ACE)基因插入/缺失(I/D)多态性与新疆汉族人群乳腺癌的相关性, 按维吾尔医将乳腺癌患者分为4 种体液型, 采用聚合酶链式反应(PCR)技术对新疆汉族139 例乳腺癌患者和72 例正常对照组ACE 基因I/D 多态性进行检测, 比较各组间等位基因和基因型频率分布的差异。结果显示, 异常黏质乳腺癌患者组II 基因型频率(P=0.018)和I 等位基因频率(P=0.004)都显著高于正常对照组;异常黏液质乳腺癌患者组I 等位基因频率显著高于异常黑胆质乳腺癌患者组(P=0.012)。由此得出, ACE 基因I 等位基因和II 基因型可能增加新疆汉族维吾尔医异常黏液质型乳腺癌的发病风险。     

Mechanisms of inherited cancer susceptibility

A small proportion of many cancers are due to inherited mutations in genes, which result in a high risk to the individual of developing specific cancers. There are several classes of genes that may be involved： tumour suppressor genes, oncogenes, genes encoding proteins involved in DNA repair and cell cycle control, and genes involved in stimulating the angiogenic pathway. Alterations in susceptibility to cancer may also be due to variations in genes involved in carcinogen metabolism. This review discusses examples of some of these genes and the associated clinical conditions caused by the inheritance of mutations in such genes.     

基于隧道机制实现H.323中防火墙和NAT的穿越

针对H.323协议与防火墙和NAT设备共处时的问题及现有解决方案的不足,提出了一种建立在运输层协议上的隧道穿越技术的解决方案：隧道机制逻辑上由客户和服务器端两部分组成,采用Socks、V5协议在客户端和服务器之间建立一条或多条TCP／UDP隧道,并制订了客户端和服务器端的工作规则,从而使H.323通信中的各种信令和媒体数据流能透明的穿越防火墙和NAT设备．仿真结果表明,相比其他解决方案,本方案可以更好地解决H．323通信中穿越防火墙和NAT设备这一问题。     

Lys751Gln polymorphism in ERCC2 gene is associated with lung cancer susceptibility in the Chinese population

The excision repair cross-complementing group 2(ERCC2)gene encodes a DNA repair protein,which is absolutely necessary in nucleotide excision repair.A polymorphism in codon 751 that induces a Lys→Gln substitution has been suggested to reduce the DNA repair capacity.Therefore,we conducted a matched case-control study to investigate the role of ERCC2 Lys751Gln polymor- phism in the development of lung cancer in the Chinese population.The genotype of ERCC2 gene was analyzed by di-allele-specific-amplifi- cation with artificially modified primers(diASA-AMP)in 200 original lung cancer cases and 200 controls.The results showed that carriers of Lys/Gln and Gln/Gln genotypes had a 3.32-fold higher risk of lung cancer compared with carriers of Lys/Lys genotype.Furthermore, the mutant genotypa of 751Gln allele was found to be associated with an increased risk in both lung squamous cell carcinoma and lung ade- nocarcinoma.However,no significant interaction between 751Gln variants and smoking was observed after stratifying according to the smoking status in this study.The results suggest that the Lys751Gln polymorphism in ERCC2 gene is a potential biomarker for suscepti- bility of lung cancer in the Chinese population.     

Lys751Gln polymorphism in ERCC2 gene is associated with lung cancer susceptibility in the Chinese population

The excision repair cross-complementing group 2 (ERCC2) gene encodes a DNA repair protein, which is absolutely necessary in nucleotide excision repair. A polymorphism in codon 751 that induces a Lys→Gln substitution has been suggested to reduce the DNA repair capacity. Therefore, we conducted a matched case-control study to investigate the role of ERCC2 Lys751Gln polymorphism in the development of lung cancer in the Chinese population. The genotype of ERCC2 gene was analyzed by di-allele-specific-amplification with artificially modified primers (diASA-AMP) in 200 original lung cancer cases and 200 controls. The results showed that carriers of Lys/Gln and Gln/Gln genotypes had a 3.32-fold higher risk of lung cancer compared with carriers of Lys/Lys genotype. Furthermore, the mutant genotype of 751Gln allele was found to be associated with an increased risk in both lung squamous cell carcinoma and lung adenocarcinoma. However, no significant interaction between 751Gln variants and smoking was observed after stratifying according to the smoking status in this study. The results suggest that the Lys751Gln polymorphism in ERCC2 gene is a potential biomarker for susceptibility of lung cancer in the Chinese population.     

甘薯种质资源亲缘关系SRAP标记分析

利用SRAP标记技术对86份甘薯品种亲缘关系进行了分析,实验选用了30对SRAP引物组合,每个引物组合分别产生10～40个扩增带,30对引物共产生了87个多态性条带,平均每对引物组合产生2.9个多态性条带.在遗传距离（GD）为0.81处,可将86个甘薯品种分为A、B、C、D四类.A类包含77个品种,占全部实验材料的89%.结合材料来源的分析结果表明,四川省育成的甘薯种质资源大多聚在一类,表明我省育成的甘薯品种资源的遗传范围还较为狭窄.     

甘肃3个特有少数民族回族和汉族DYS287 DYS19的遗传多态性研究

以中国甘肃的3个特有少数民族,天水汉族、天水回族、临夏回族6人群为研究对象,采用RCR技术及变性聚丙烯酰胺凝胶电泳法,分析了高变染色体特异的微卫星DYS19的等位基因分布规律,共检出7种等位基因.甘肃3个特有少数民族DYS19的等位基因频率存在显著性差异(P＜0.05).通过PCR方法调查了Alu元件插入基因座DYS287的多态性.结果显示,除保安族没有发现Alu插入外,其他人群均发现Alu插入,其中临夏回族表现了较高的插入频率(12.9%).MDS分析表明:裕固族和汉族的遗传关系比较接近,6人群遗传距离和空间距离没有明显的相关性.     

河南汉族人群 4个Y-STR基因座及单倍型遗传多态性分析

采用 PCR扩增和非变性聚丙烯酰胺凝胶电泳及DNA序列分析河南汉族102名无血缘关系、健康男性个体的4个Y-STR基因座基因及单倍型频率分布.结果显示：4个基因座共发现了24个等位基因,频率分布在0.0098～0.7745. 102个个体共检测到55个单倍型 ,单倍型多样性为0.8939.