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91.
To discern the ethical issues involved incurrent gene therapy research, to explore theproblems inherent in possible future genetherapies, and to encourage debate within thescientific community about ethical questionsrelevant to both, we surveyed American Societyof Human Genetics scientists who engage inhuman genetics research. This study of theopinions of U.S. scientific experts about theethical issues discussed in the literature ongene therapy contributes systematic data on theattitudes of those working in the field as wellas elaborative comments. Our survey finds thatrespondents are highly supportive of thepotential use of somatic cell gene therapy tocure serious diseases in adults and children aswell as prospective offspring. A clearmajority, however, believe that using suchgenetic techniques for enhancement purposes isunacceptable. Delineating the line betweendisease/disorder and improvement/enhancementposes a problem not easily resolved and oneconducive to the growth of slippery-slopeapprehensions. The majority of respondents alsoadvocate germ-line therapy, in theory at least,and under similar restrictions, but theyrecognize the roadblock that the existence ofunanticipated negative consequences currentlypresents. Another complex matter involvestrying to determine appropriate reasons forchoosing target diseases for research, forwhich the dichotomy between rare single-geneand common multifactorial diseases reveals anongoing dilemma.  相似文献   
92.
“遗传与环境”的争论一直是创造力研究的核心问题, 但目前对于环境以及遗传与环境交互作用对创造力影响的分子生物机制还未有研究涉及。近年来, 随着表观遗传学的兴起, 揭示影响心理行为的表观遗传机制现已成为心理学研究的热点。作为环境与基因组之间的纽带, 表观遗传学研究为揭示环境以及遗传与环境交互作用对创造力影响的分子生物机制提供了机遇。本研究以多巴胺相关基因、家庭环境以及两者对于创造力的交互作用为切入点, 对影响创造力的表观遗传机制进行考察, 并在此基础之上, 对环境以及遗传与环境交互作用对创造力影响的分子生物机制进行探索。具体研究内容包括:(1)通过对多巴胺相关基因甲基化模式与创造力关系的系统考察, 筛选出甲基化模式与创造力有关的基因; (2)对筛选出的基因, 进一步考察其甲基化模式在家庭环境及其遗传多态性与家庭环境交互作用对创造力影响中的中介作用。本研究有助于揭示创造力的表观遗传机制, 深化关于遗传与环境对创造力影响的作用机制的理解。  相似文献   
93.
迄今,有关抑郁的基因×环境交互研究多数基于“单胺缺陷假说”,相对较少有研究以“HPA轴假说”为框架考察抑郁的遗传机制,且忽视了基因-环境相关的影响。本研究对1081名青少年进行追踪研究,考察NR3C1基因Bcl1多态性与压力性生活事件对抑郁的影响。结果发现,经历较多压力性事件时,C等位基因携带者的抑郁水平显著高于GG纯合子携带者;经历较少压力性事件时,不同基因型携带者的抑郁水平无差异。此外,通过区分独立性压力性事件和预测早期抑郁进一步排除了基因-环境相关的影响,在一定程度上验证了结果的可靠性。  相似文献   
94.
Whether differences in personality among populations really exist and, if so, whether they are only due to cultural and linguistic differences or have a genetically selected adaptive value, is a controversial issue. In this research, we compared three Italian populations living on three small archipelagos in the Tyrrhenian Sea (n = 993), with their corresponding neighbouring mainlanders (n = 598), i.e. sharing the same geographical origin, culture and language. We used an adjective‐based Big Five questionnaire in order to measure personality traits in four categories of individuals for each archipelago/mainland population: (1) original islanders; (2) non‐original islanders; (3) mainlanders and (4) immigrants to the islands. We further analysed original and non‐original islanders who had or had not emigrated from the islands. We found that islanders had different personality traits from mainlanders, the former being more conscientious and emotionally stable and less extraverted and open to experience. We also found that the subgroup of islanders whose ancestors had inhabited their island for about 20 generations in isolation (original islanders, n = 624) were less extraverted and open to experience than immigrants (n = 193). In contrast, immigrants retained the typical personality profile of the mainland populations. Lastly, emigrants from the islands (n = 209) were significantly more extraverted and open to experience than original and non‐original islanders who had never left their island (n = 741). We hypothesise that population differences in extraversion and openness to experience are more probably related to genetic differences which evolved rapidly, presumably through an active gene flow produced by selective emigration from the islands. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
95.
耳聋基因治疗进展及评价   总被引:2,自引:1,他引:1  
基因治疗为感音性聋的治疗提供新的生物治疗模式,通过预防毛细胞死亡、调控毛细胞分化和再生、基因操纵、干细胞移植、RNA干扰等手段而恢复内耳功能。耳聋基因治疗体现了多学科联合发展的要求及求异性思维的重要性,但仍面临诸多问题,从哲学的角度思考及正确对待耳聋基因治疗,必将有利于促进该技术最终服务于人类。  相似文献   
96.
Focal lacunar infarctions due to cerebral small vessel atherosclerosis or single/multiple large cortical infarcts lead to vascular dementia, and different genes and environmental factors have been implicated in causation or aggravation of the disease. Previous reports suggest that some of the risk factors may be common to both vascular as well as degenerative dementia. Among genetic factors, role of angiotensin converting enzyme (ACE) and methylene-tetrahydrofolate reductase (MTHFR) genes as putative risk factors has been examined but the outcome of these studies remain inconclusive. Present study attempted to see the importance of ACE alu insertion/deletion and MTHFR C677T polymorphisms as genetic predisposers to dementia. The study comprised of 80 vascular dementia patients, 90 degenerative dementia patients and 170 age matched controls. All were genotyped for ACE, MTHFR and APOE polymorphisms using PCR-RFLP method. Frequency of ACE D allele was seemingly high in dementia cases (26.7%) when compared to controls (11.2%). However, after adjusting for age and APOE E4*, none of the ACE alleles showed good correlation. MTHFR genotypes or alleles also did not show any correlation. Our study suggests no true correlation of ACE or MTHR genes with dementia in elderly.  相似文献   
97.
The concept of regression is considered with an emphasis on the differences between the positions of Freud and Jung regarding its significance. The paper discusses the results of experimental analyses of individual experience dynamics (from gene expression changes and impulse neuronal activity in animals to prosocial behaviour in healthy humans at different ages, and humans in chronic pain) in those situations where regression occurs: stress, disease, learning, highly emotional states and alcohol intoxication. Common mechanisms of regression in all these situations are proposed. The mechanisms of regression can be described as reversible dedifferentiation, which is understood as a relative increase of the representation of low-differentiated (older) systems in the actualized experience. In all of the cases of dedifferentiation mentioned above, the complexity of the systemic organization of behaviour significantly decreases.  相似文献   
98.
羞怯是指社交情境中的不舒服和/或者抑制,会妨碍个体对人际目标或职业目标的追求;表现为过分地自我关注、全神贯注于个人的想法,以及某些情绪和生理的反应.近几年,从行为遗传学的角度探讨羞怯的成因成为该领域研究的前沿与热点.早期的双生子研究与分子遗传学的研究结果表明,羞怯与遗传密切相关;5-HTTLPR短型基因与羞怯的关系尤为密切;羞怯可能是多种基因以及基因与环境交互作用的结果.  相似文献   
99.
肿瘤是当今人类生命健康的主要威胁之一。致癌基因与遗传背景和肿瘤的形成有密切关系。致癌基因与遗传背景,致癌基因与抗癌基因之间的时空结构和非线性作用都有可能使正常细胞恶变,导致肿瘤的形成。致癌基因与遗传背景实际上构成了细胞中的一个完整的遗传系统。本文试图用系统方法探讨两者的相互作用,以便更好地探讨肿瘤发生的机理和治疗手段。  相似文献   
100.

基因编辑婴儿事件暗示了预防医学和人类增强之间存在某些联系。预防医学以相对明确的潜在疾病为对象,通过增强人体抵抗疾病的能力从而减少或避免由疾病产生的既得利益损失。人类增强以人类的某种特性为对象,通过增强这些特性或保持这些特性的最佳状态,从而获得额外收益或避免既得利益的损失。在“对象−方法−目的”模型下,预防医学和人类增强表现得极为相似,并且在诉求、技术、概念和形而上学方面的相互交错也进一步模糊了两者之间的界线。然而,人类增强完全市场化分配制度及其对公平的固有破坏性是它与预防医学之间的一个根本区别。

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