生殖隔离形成机理的杂合子低适合度分化模型  

Differentiation Modeling of Heterozygote with Low Fitness Based on the Formation Mechanism of Reproductive Isolation

作　　者：韦文惠[1] 

机构地区：[1]柳州职业技术学院,广西柳州545006

出　　处：《安徽农业科学》2010年第13期7148-7149,7174,共3页Journal of Anhui Agricultural Sciences

基　　金：广西教育厅科研项目(200807MS065);广西高校优秀人才资助计划项目"群体遗传中的数学建模"

摘　　要：通过用RR、Rr和rr3种基因型的适合度之比,量化R与r基因在后代中的频率,计算r的频率逐代演变的分岔点,研究随机交配群体中的杂合子适合度低于纯合子适合度的突变基因r在群体中的逐代积累过程。揭示了R与r在遗传中的不相容性;遗传漂变能使r在新群体中有较高的频率,超过分岔点,最终形成生殖隔离;同时生物进化的动力仅有突变、遗传漂变、自然选择这3个条件还不够,还需要有杂合子适合度低于纯合子适合度的突变基因,即原有群体的遗传背景对新突变的排斥作用。According to the fitness of heterozygote was lower than homozygote among panmictic population, the process of generational accumulate of mutant gene r was considered. Branch point of r’ s frequency by generational evolution which revealed the hereditary incompatibility between R and r, was worked out, and it was found that genetic drift could make r has higher frequency to surpass the branch point to form reproductive isolation. It was not enough to have the three conditions of mutation, genetic drift and natural selection to be the drive of biological evolution; hybrid weakness, the repelling interaction between the genetic background of original population and the new mutation, were also needed.

关 键 词：生殖隔离 适合度 突变基因 杂合子 分岔点 

分 类 号：S188[农业科学—农业基础科学]