警惕啊!基因决定论

基因已经成为２０世纪遗传学中的一个关键词基因决定论也正在走近我们的生活本文从遗传学的角度阐述了基因决定论的种种不当之处,并且指出基因的作用与人类的生活方式密切相关,而人类的全部文明史就在于克服单纯的基因决定论所带来的局限。     

Molecular carrier testing for the fragile X syndrome: Issues for genetic counselors

Molecular analysis of the fragile X (FMR-1) gene identifies female fragile X carriers, but appropriate genetic counseling can only be provided if the limitations of the testing methods are understood. Molecular analysis of this gene is achieved with both the polymerase chain reaction (PCR) and Southern blot techniques. PCR is faster and can determine the actual number of CGG repeats, which modifies genetic counseling substantially. However, for a sizeable percentage of women, PCR alone is not conclusive, and Southern analysis is necessary to complete the study. While this procedure takes longer, it is usually conclusive. Women who present for genetic counseling and carrier testing in the second trimester of pregnancy need this information quickly, and for them the turn-around time is paramount. It is critical that genetic counselors understand these methods so that they can educate their clients and facilitate appropriate follow-up.     

COMT基因rs6267多态性与青少年期亲子亲合与冲突的关系：性别与父母教养行为的调节作用分析

采用基因－环境设计, 以208名初中生为被试, 系统考察COMT基因rs6267多态性与青少年期亲子亲合与冲突的关系, 以及性别与父母教养行为在其中的调节作用。结果显示rs6267多态性对亲子关系无显著主效应, 但其与亲子亲合、母子情绪冲突的关联模式在男女青少年群体中相反; rs6267多态性与父母积极教养行为对亲子关系无显著交互作用, 但其与母亲消极教养行为对母子冲突具有交互作用趋势。     

RNAi的曲折经历与发展

RNAi是当今分子生物学研究领域内最引人注目的技术之一.已经在植物、线虫、果蝇、锥虫甚至哺乳动物细胞中发现RNAi现象. RNAi同时也是体内抵御病毒入侵、抵抗外在感染和抑制转座子活动的一种重要保护机制.通过介绍RNAi 技术富有传奇色彩的诞生和发展过程以及它对分子生物学乃至整个生命科学界产生的巨大作用,认识到RNAi是多学科联合发展的结果.我们应该加强各学科之间的整合.     

MAOA基因T941G多态性与同伴侵害对男青少年早期抑郁的交互作用:COMT基因Val158Met多态性的调节效应

抑郁具有复杂的多基因遗传基础,然而既有研究大多采用单基因以及单基因-环境交互设计(G×E)考察抑郁的遗传机制。以757名男青少年为被试(初次测评时Mage=11.32岁,SD=0.49岁),采用多基因-环境交互(G×G×E)设计,本研究考察了MAOA(monoamine oxidase A,单胺氧化酶A)基因T941G多态性、COMT(catechol-O-methyltransferase,儿茶酚胺氧位甲基转移酶)基因Val158Met多态性与同伴侵害对青少年早期抑郁的影响。结果显示,MAOA基因T941G多态性与同伴侵害交互作用于青少年抑郁,同伴侵害仅显著正向预测G等位基因(而非T等位基因)青少年抑郁。而且,MAOA基因T941G多态性与同伴侵害的交互作用受到COMT基因Val158Met多态性的调节,上述交互作用仅存在于COMT Met等位基因而非Val/Val基因型携带者中。研究结果显示,抑郁的产生与个体差异存在多基因与环境间的复杂交互机制。     

Emotional Reaction to Fragile X Premutation Carrier Tests Among Infertile Women

Female fragile X premutation carriers are at ∼10-fold increased risk of premature ovarian failure (follicle stimulating hormone >40 mIU/mL, amenorrhea, age <40). A milder degree of premature ovarian aging (diminished ovarian reserve, where follicle stimulating hormone levels are typically 10–20 mIU/mL) results in infertility. Approximately 10% of fertility clinic patients have this diagnosis. A cohort of 20 women diagnosed with diminished ovarian reserve provided a blood specimen (confidential results), and completed structured questionnaires that assessed emotional reactions to potentially being a premutation carrier (pretest questionnaire, n = 20) and the posttest known carrier status (3 month follow-up questionnaire, n = 18 non-carriers). Responses were measured using 9-point scales, and analyzed with Fisher exact and Wilcoxon exact tests. While most participants did not view fragile X premutations as a serious medical condition, perceptions of seriousness were positively correlated with anger and regret about not knowing sooner of the potential association of these premutations with infertility. Overall, when women (pretest) imagined themselves as carriers, their self-esteem and Health Orientation Scale responses were unchanged with the exception of feeling more afraid (p = 0.004). Despite strongly wishing for negative test results, they were glad to know there might be a medical explanation for their infertility. Financial Support: This work was financially supported by a University of Virginia School of Medicine Research & Development Award.     

Yesterday’s Child: How Gene Editing for Enhancement Will Produce Obsolescence—and Why It Matters

Despite the advent of CRISPR, safe and effective gene editing for human enhancement remains well beyond our current technological capabilities. For the discussion about enhancing human beings to be worth having, then, we must assume that gene-editing technology will improve rapidly. However, rapid progress in the development and application of any technology comes at a price: obsolescence. If the genetic enhancements we can provide children get better and better each year, then the enhancements granted to children born in any given year will rapidly go out of date. Sooner or later, every modified child will find him- or herself to be “yesterday’s child.” The impacts of such obsolescence on our individual, social, and philosophical self-understanding constitute an underexplored set of considerations relevant to the ethics of genome editing.     

负性生活事件与青少年早期抑郁的关系：COMT基因Val158Met多态性与父母教养行为的调节作用

采用环境×基因×环境(E×G×E)研究设计, 以637名青少年为被试, 考察了负性生活事件、COMT基因Val158Met多态性和父母教养行为对青少年早期抑郁的影响。结果发现：负性生活事件对青少年早期抑郁具有显著正向预测作用, 且COMT基因Val158Met多态性和父亲积极教养行为在其中起调节作用, 但该调节作用仅存在于男青少年群体中：在携带Val/Val基因型的男青少年中, 当父亲积极教养行为水平较低时, 青少年的抑郁水平随负性生活事件的增多而显著上升, 当父亲积极教养行为水平较高时, 负性生活事件对抑郁无显著预测作用; 在携带Met等位基因的男青少年中, 上述交互作用不显著。     

情绪应激对不同脑区c-fos表达的影响

利用电击信号和空瓶刺激两种情绪应激体液免疫调节作用动物模型,以c-fos原癌基因为探针,观察情绪应激后2个小时,大鼠全脑的c—fos原癌基因表达情况,探讨情绪应激对不同脑区c—fos表达的影响。结果表明,电击信号和空瓶刺激两种情绪应激源均能引起某些脑区或核团的c—fos蛋白表达明显增加,包括额皮质、扣带皮质、杏仁内侧核、前连合核、下丘脑背内侧核弥散部、弓状核、孤束核。结果提示,这些脑区或核团是情绪应激主要激活的中枢部位。     

血液肿瘤的基因治疗及伦理学问题

基因治疗是一种新的有希望的抗肿瘤治疗方法。本文首先简述基因治疗发展史,然后介绍目前尝试性用于血液系统肿瘤的反义核酸疗法、抑癌基因疗法、自杀基因疗法以及过继性免疫疗法等基因治疗方法,进一步阐述基因治疗在血液系统肿瘤患者中应用存在的伦理学问题。