Department of Biology, The College of Wooster, Wooster, Ohio 44691.
Genetics. 1983 May;104(1):95-112. doi: 10.1093/genetics/104.1.95.
Several stocks, selected because they carried previously identified factors governing either crossing over in males or mutability, were examined to determine whether the effects of these factors are restricted to one or the other process. Neither of two dominant enhancers of male crossing over had detectable effects on Minute mutation frequencies among progenies of assayed F(1) males. Genetically equivalent F(1) males monitored for crossing over showed no unequivocal effect of either of three mutators (two dominant and one extrachromosomal) or of a suppressor of mutability. However, one combination of a dominant crossover enhancer with a dominant mutator showed synergistic increases in both crossover and Minute frequencies, and the possibility exists that a single extrachromosomally transmitted element suppresses both male crossing over and mutability. This suppressor element (or elements) had been previously diagnosed in the pc stock which, in this study, was discovered to have also a dominant enhancer of male crossing over and a dominant mutator occupying separable loci in the third chromosome. The pc enhancer of male crossing over differs from the dominant enhancer in another stock with respect to the regional distribution of crossovers, and the pc mutator is distinguished from another 3-linked mutator by its preferential induction of mutations at the Delta locus.
选择了几种品系进行研究，因为它们携带先前确定的控制雄性交叉或突变的因素，以确定这些因素的影响是否仅限于一个过程。两种显性雄性交叉增强子都没有对检测到的 F1 雄性后代的 Minute 突变频率产生可检测的影响。对监测交叉的遗传等效 F1 雄性没有发现三个突变体（两个显性和一个染色体外）或一个突变抑制因子的任何明确影响。然而，一种显性交叉增强子与显性突变体的组合表现出交叉和 Minute 频率的协同增加，并且存在一种可能性，即单个染色体外传递的元件抑制雄性交叉和突变性。这个抑制因子（或多个）之前在 pc 品系中被诊断出来，在这项研究中，发现它还具有显性雄性交叉增强子和占据第三染色体分离位点的显性突变体。pc 雄性交叉的增强子与另一个品系中的显性增强子在交叉的区域分布上不同，pc 突变体与另一个 3 号染色体上的突变体不同，它优先诱导 Delta 位点的突变。
