Hall J G, Wills C
Department of Biology C-016, University of California at San Diego, La Jolla 92093.
Genetics. 1987 Nov;117(3):421-7. doi: 10.1093/genetics/117.3.421.
Documented examples of heterosis attributable to overdominance at specific protein-encoding gene loci have rarely been reported, the association of sickle cell hemoglobin with malarial resistance being the best documented example of this phenomenon. Here we report an example of overdominance that is temperature- and allyl alcohol-dependent and due to heterozygosity at the ADH1 locus, involving two ADHI functional mutants. Overdominance appears to be due in part to an intermediate level of ADHI activity in the heterozygote. Unlike previous work with this this system using haploid strains, the NAD+/NADH ratios show no negative correlation with allyl alcohol resistance. This system is formally equivalent to that of sickle cell hemoglobin and shows promise as a tool for investigating the physiological basis for overdominance.
归因于特定蛋白质编码基因座超显性的杂种优势的实例鲜有文献记载，镰状细胞血红蛋白与疟疾抗性的关联是该现象记载最为详尽的例子。在此，我们报告一个超显性的例子，它依赖于温度和烯丙醇，并且由于ADH1基因座的杂合性，涉及两个ADHI功能突变体。超显性似乎部分归因于杂合子中ADHI活性的中间水平。与之前使用单倍体菌株对该系统的研究不同，NAD+/NADH比率与烯丙醇抗性没有负相关。这个系统在形式上等同于镰状细胞血红蛋白系统，有望成为研究超显性生理基础的工具。
