Engineered underdominance allows efficient and economical introgression of traits into pest populations
Engineered underdominance allows efficient and economical introgression of traits into pest populations
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DOI：
10.1006/jtbi.2001.2357
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发表时间：
2001-09-07
影响因子：
2
通讯作者：
Grewe, P
中科院分区：
文献类型：
--
作者：
Davis, S;Bax, N;Grewe, P
一种新形式的欠显性被认为是一种机制，能够驱动所需的基因进入害虫种群通过释放转基因个体在一个或多个世代。那些致力于通过释放对疟疾寄生虫不敏感的疟疾病媒按蚊菌株来减少疟疾影响的人迫切需要这样一种机制。我们使用简单的群体遗传学模型来量化杂合基因型时所带来的好处，从引进和野生个体之间的交配，是不可行的。在一个随机交配的群体中，弱显性系统加速了所需等位基因的渐渗，并允许一旦转基因等位基因的频率达到阈值就停止个体的释放。一组两个结构，这两个结构在一起是选择性中性的，但致命的，当一个是没有其他进行，被发现产生动态的特征是欠主导系统。当这些构建体携带在非同源染色体上时，则释放的个体与天然出生的个体的比率仅需要大于3：100就发生基因渗入。此外，预期在停止释放转基因个体时引入的基因变得固定的基因频率的阈值令人惊讶地低。阈值的位置表明，引入的基因预计将在空间中传播，至少在局部。首次提出了害虫种群遗传操作的实用驱动机制的前景。(C)北京：科学出版社.
A novel form of underdominance is suggested as a mechanism that is able to drive desired genes into pest populations through the release of transgenic individuals over one or more generations. Such a mechanism is urgently needed by those working to reduce the impact of malaria by releasing strains of Anopheles, the vector of the disease, that are not susceptible to malaria parasites. We use simple population genetics models to quantify the benefits conferred when heterozygous genotypes, arising from matings between introduced and wild individuals, are not viable. In a randomly mating population, underdominant systems accelerate introgression of desired alleles and allow the release of individuals to be discontinued once the frequency of transgenic alleles attains a threshold. A set of two constructs, which together are selectively neutral but lethal when one is carried without the other, are found to produce dynamics that are characteristic of underdominant systems. When these constructs are carried on non-homologous chromosomes, then the ratio of released to natural born individuals need only be greater than 3: 100 for introgression to occur. Furthermore, the threshold for the gene frequencies over which the introduced genes are expected to become fixed upon discontinuing the release of transgenic individuals is surprisingly low. The location of the threshold suggests that the introduced genes are expected to spread in space, at least locally. For the first time, the prospect of a practical drive mechanism for the genetic manipulation of pest populations is raised. (C) 2001 Academic Press.