XRCC1多态性与非吸烟女性肺腺癌易感性的关系

背景与目的XRCC1是一种DNA损伤修复基因，其单核苷酸多态性异常是导致DNA修复能力个体差异的重要原因，可能导致个体患肺癌的危险升高。本研究的目的是探讨XRCC1单核苷酸多态性与非吸烟女性肺腺癌易感性的关系。方法采用以医院患者为基础的病例对照研究方法，研究对象包括非吸烟女性肺腺癌患者126例和同期其它肺部疾病对照126例。以聚合酶链反应一限制性片段长度多态性方法分析XRCC1基因Arg399Gln多态性，比较不同基因型与非吸烟女性肺腺癌的关系，并探讨油烟暴露与基因多态交互作用对患癌风险的影响。结果与携带399Arg／Arg基因型者比较，携带399Gln／Gln基因型者患肺腺癌的风险是其8．695倍（95％CI为3．343～22．614）。携带等位基因399Gln又有油烟暴露的个体患肺腺癌的风险明显增高，校正的比值比为5．21（95％CI为1．85～14．70，P〈0．001）。结论XRCC1基因Arg399 Gln多态性可能是非吸烟女性肺腺癌的遗传易感因素。     

肠激酶特点及其基因工程的研究进展

肠激酶是从哺乳动物体内提取的一种丝氨酸蛋白酶,广泛应用于基因T程领域切割融合蛋白。文章对肠激酶的特点及其基因工程研究进展进行了综述。     

河南省Ⅱ型汉坦病毒基因亚型及其分布的研究

目的查明河南省Ⅱ型汉坦病毒基因亚型的分布情况。方法在河南省汉坦病毒流行严重的地区，捕捉啮齿类动物，以免疫荧光法检测阳性标本，应用汉坦病毒型特异性引物以逆转录，聚合酶链反应方法对抗原检测阳性的鼠肺标本扩增M和S基因片段上的特异核苷酸序列并测序，将扩增片段的核苷酸序列与已知病毒序列进行比较，以明确基因亚型及其地理分布情况。结果褐家鼠、黄胸鼠以及小家鼠携带的病毒均为Ⅱ型汉坦病毒。序列分析发现河南省主要疫区宿主动物问流行的Ⅱ型汉坦病毒至少存在S1、S2和S3三个亚型，其中S1和S3为河南省汉坦病毒的优势流行基因亚型。结论河南省汉坦病毒的亚型较为复杂，地理分布较广。     

江苏省现阶段麻疹流行株H1基因型

目的监测现阶段在江苏省流行的麻疹野病毒及其基因型别.方法 2003年5月分别在医院门诊疑似麻疹病人和疑似麻疹爆发点的病人中采集了咽拭子,接种EB病毒转化的绒猴淋巴母细胞(B95a细胞),获得3株麻疹野病毒,同时进行了血球凝集(HA)试验、血球吸附试验.结果该3株病毒均无HA和血球吸附活性,逆转录-聚合酶链反应和其产物的基因序列分析提示,这3株病毒属于麻疹野病毒第8基因组H1基因型.结论此次为江苏省首次分离到麻疹野病毒,并证实在江苏省流行的麻疹野病毒基因型与国内流行优势基因型相同.     

Molecular serotonergic mechanisms appear to mediate genetic sensitivity to cocaine-induced convulsions

Cocaine-induced convulsions appear to be mediated by serotonin (5-HT) neurotransmission, acting primarily at 5-HT(2) receptors. However, this effect of cocaine is attenuated by cocaine binding at sigma and muscarinic M(1) and M(2) sites. This study examined whether the aforementioned neural sites mediate the nearly two-fold difference in sensitivity to cocaine-induced convulsions across C57BL/6J (6J) and C57BL/6ByJ (6ByJ) mice. Experiment 1 compared 5-HT transporter densities across several brain regions of 6J and 6ByJ mice and cocaine-induced convulsions following pretreatment with the 5-HT reuptake inhibitor fluoxetine. Experiment 2 compared 5-HT(2) receptor densities across these mice and cocaine-induced convulsions following pretreatment with the 5-HT(2) antagonist cinanserin. There were no differences in 5-HT transporter densities, however, fluoxetine produced a greater facilitation of cocaine-induced convulsions in 6ByJ relative to 6J mice, suggesting that sensitivity to convulsions is mediated postsynaptically. Indeed, 5-HT(2) density was higher in 6ByJ relative to 6J mice in the amygdaloid ridge, hypothalamus, and midbrain. In addition, cinanserin attenuated convulsions more potently in 6J relative to 6ByJ mice. There were no differences in the densities or affinities of 5-HT(1), muscarinic, or sigma receptors across these strains, suggesting that density of these latter sites does not mediate genetic sensitivity to cocaine-induced convulsions. Since 6ByJ mice are less sensitive to convulsions despite the fact that they have more 5-HT(2) receptors, we hypothesized that these mice may exhibit a weaker linkage of 5-HT(2) sites to their second-messenger system relative to 6J mice. However, in experiment 3 we demonstrated that 5-HT(2)-receptor mediated phosphoinositide hydrolysis was higher in 6ByJ relative to 6J mice in the same regions also displaying higher 5-HT(2) densities. This study suggests that 5-HT(2) receptors mediate genetic sensitivity to cocaine-induced convulsions, further supporting the role of these sites in mediating this toxic effect of cocaine.     

Interaction and Relationship Between Angiotensin Converting Enzyme Gene and Environmental Factors Predisposing to Essential Hypertension in Mongolian Population of China

Objective To investigate the association of specific functional gene ACE (I/D) variants of the renin-angiotensin system with essential hypertension (EH) and interaction between ACE (I/D) gene and risk factors for EH in a genetically homogenous Mongolia rural population of China. Methods Individuals (n=1099) were recruited from general population of Kezuohouqi Banner in Inner Mongolian Autonomous Region. Results The association was found between ACE genotype DD plus ID and EH, with an interaction between ACE genotype DD plus ID and cigarette smoking in an additive model. Cigarette smoking index and ACE gene showed a low exposure-gene (LEG) effect on EH, with interaction indices from 7.10 to 1.16. Interaction between ACE genotype DD plus ID and alcohol drinking on EH appeared an additive model. Alcohol drinking index and ACE gene showed a low exposure-gene (LEG) effect on EH, with interaction indices from 1.66 to 1.09. BMI and ACE gene showed a low exposure-gene (LEG) effect on EH, with interaction indices from 6.15 to 2.49.Interactions between ACE genotype and WHR on EH showed a multiplicative model. In a short, there was an interaction between ACE gene and cigarette smoking, alcohol drinking and BMI on EH,especially in a low dose-exposure effect.Cpmchusion It is important for individuals who carry ACE D allele gene to prevent FH, and furthermore, to prevent and control coronary heart disease, in a view of population-based prevention.     

广西省百色市地中海贫血干预模式初探

目的:初步探讨广西省百色市地中海贫血干预模式。方法:在干预区进行地中海贫血的宣传、遗传咨询活动,提供地中海贫血筛查和产前诊断服务,并在干预前后对调查对象进行问卷调查。结果:调查对象的地贫基本知识及态度的基线答对率为(44±6.7)％(10％～92％),干预后答对率为(81±5.8)％(62％～96％),干预前后有显著性差异(P<0.01)。干预组进行地贫筛查例数为630/700(90％)。干预后进行产前诊断25例(年均8.33例),比干预前年均增加4例(P<0.05)。干预后促进的产前诊断比干预前提高了37％,每2.7例产前诊断就有1例是由于预措施促成,并避免了4例重型地贫儿的出生。结论:干预后妊娠高危胎儿孕妇进行产前诊断例数提高,干预效果明显。     

GSTM1及GSTT1基因多态性与宫颈癌关系的研究

目的：探讨GSTM1及GSTT1基因多态性与宫颈癌发生的关系.方法：采用以医院为基础的病例对照及分子流行病学研究方法,应用多重PCR技术检测125例宫颈癌病例和125例子宫肌瘤对照的GSTM1和GSTT1基因型.结果：病例组GSTM1基因纯合缺失率为58.4%,显著高于对照组43.2%（x^2=5.777,P=0.016）;GSTT1基因纯合缺失率在病例组和对照组分别为53.6%和44.0%,差别无统计学意义（x^2=2.305,P=0.129）;GSTM1和GSTT1联合缺失者患宫颈癌的危险性是两基因同时存在者的2.588倍（95%CI=1.285～5.212）.结论：GSTM1基因纯合缺失或GSTM1、GSTT1联合缺失可能与宫颈癌的发生有关.     

植入前遗传学诊断"知情同意"的影响因素与对策

植入前遗传学诊断（Preimplantation Genetic Diagnosis PGD）是辅助生育技术与分子生物学技术相结合而发展的孕前遗传学诊断技术,在植入子宫前淘汰了遗传异常的胚胎,是产前诊断技术的重大进展.但是,由于技术本身存在着一定局限性和不确定性,同时,受到病人认知能力等因素的影响,由此引发了系列伦理学争议.在进行PGD前,一个明了、详尽的患者知情同意过程是必须的.包括通俗全面告知PGD有关信息、手术和检测的局限性和可能结果;充分告知通过PGD所获得的利益和风险.在此基础上针对不同的遗传病检测签署详细的书面知情同意书.     

XRCC1单核苷酸多态及单体型分布与乳腺癌的相关研究

目的：探讨X线交叉互补基因1（XRCC1）外显子C26304T、G27466A和G28152A三处最常见的单核苷酸多态性（single nucleotide polymorphism，SNP）与乳腺癌的关系。方法：以自然人群为基础的病例对照研究方法，对84例乳腺癌患者组和以1：3成组频数匹配原则获得的252例对照组进行研究，XRCC1 C26304T、G27466A和G28152A SNPs基因分型采用聚合酶链反应-限制性内切酶片段长度多态性（polymerase chain reaction—restriction fragment length polymorphism，PCR—RFLP）分析方法。单体型分布采用EH linkage software 1．2分析软件进行预测和比较。结果：乳腺癌患者组和对照组吸烟状况分布差异有显著性，病例组曾经或现在吸烟个体比例7．1％明显高于对照组2．0％（P〈0．05），性别、年龄、饮酒状况及一二级亲属家族恶性肿瘤史等基本特征因素分布差异均无显著性（P〉0．05）。C26304T、G27466A和G28152A SNPs多态基因型和多态等位基因分布在两组间分布差异均无显著性（P〉0．05）。经上述因素校正后，XRCC1 SNPs与乳腺癌发病没有显著相关关系（P〉0．05）。应用EH linkage software 1．2单体型分析软件显示，XRCC1 SNPs在各组内均存在连锁不平衡现象，CGG、CGA、CAG和TGG是最常见的4类单体型。单体型组间分布同样不存在显著性差异（P〉0．05）。结论：XRCC1 C26304T、G27466A和G28152A SNPs与乳腺癌的风险没有相关关系，各SNPs存在连锁不平衡现象，CGG、CGA、CAG和TGG是最常见的4类单体型。