MALE RECOMBINATION - MUTATOR SYSTEM IN DROSOPHILA

孟德尔的1：1隔离比例在许多理论中都被接受 种群遗传学。这个项目的长期目标是表明 “非孟德尔比率”实际上是普遍规律。这是一个明确的目标 该项目是重新建立正式的遗传基础的元素 果蝇的分离偏差(SD)系统。SD系统 一直被认为是非孟德尔式种族隔离的最佳范例之一 (减数分裂驱动)。对这一模型系统的研究将为我们提供一个很好的 为实现上述长期目标奠定基础。几款车型都有 提出用来解释偏析扭曲的过程，但不是全部 到目前为止所作的观察可以用那些令人满意的解释 模特们。在所有提出的模型中有一个共同的预测，即， 在SD杂合子RSP(不敏感)/RSP(敏感)男性中， 携带RSP(敏感)等位基因的染色体扭曲，但 染色体与RSP(不敏感)不同。然而，这一预测是 完全重温了我最近的一些观察。我暂定 将这种现象称为负分离扭曲，它出现了 质疑最基本的敏感和不敏感的概念 RSP等位基因。除了目前为止可持续发展系统的四个基本要素 在这个系统中肯定还有几个起关键作用的- 决定偏析扭曲方向的角色(至少一个 在第二条和至少一条X染色体上)。包括这些新的 元素，我计划重建种族隔离的正式遗传基础 一劳永逸地扭曲。为了做到这一点，我将采用“受精” 女性转学“试验计划，而不是采用 传统上使用的交配方案，其中只有一部分后代 进行了抽样，这样结果将为我们提供更好的估计 “绝对值”而不是“相对值”。这些措施的结果 研究将需要我们重新评估许多种群遗传学 对人类群体的预测，如因接触而造成的遗传损害 辐射和化学物质代代相传。

Mendelian 1:1 segregation ratio has been accepted in many theories in population genetics. The long-term goal of this project is to show that "non-Mendelian ratio" is in fact the general rule. Specific aim of this project is to re-establish a formal genetic basis of the elements of Segregation Distorter (SD) system in Drosophila melanogaster. The SD system has been known as one of the best examples of non-Mendelian segregation (meiotic drive). Studies on this model system will provide us with a good basis to approach the long-term goal described above. Several models have been proposed to explain the process of segregation distortion, but not all of the observations thus far made can be satisfactorily explained by those models. There is one common prediction among all the proposed models, i.e., in an Sd heterozygous Rsp (insensitive)/Rsp (sensitive) male, the chromosome carrying the Rsp (sensitive) allele is distorted, but the chromosome with the Rsp (insensitive) is not. However, this prediction was completely re-versed in some of my recent observations. I tentatively termed this phenomenon as negative segregation distortion and it appears to question the most basic concept of sensitivity and insensitivity of the Rsp alleles. Besides four basic elements of the SD system so far characterized, there must be several more in this system which play key- roles to determine the direction of segregation distortion (at least one in the second and at least one in the X chromosomes). Including these new elements, I plan to reestablish the formal genetic basis of segregation distortion once and for all. To do this, I will adopt the "inseminated female transfer" experimental scheme, instead of adopting the conventionally used mating scheme in which only a fraction of total progeny was sampled, such that the results will provide us with a better estimate of the "absolute values" but not of the "relative values". Results of these studies will require us to re-evaluate many of the population genetics predictions on human populations such as genetic damages due to exposure to irradiation and chemicals through generations.