Department of Agronomy, Iowa State University, Ames, Iowa, USA.
Theor Appl Genet. 1973 Jan;43(3-4):121-33. doi: 10.1007/BF00306561.
Chromosome interchanges were used to relocate four alleles of the wx locus in order to analyze the distribution of recombination potential of the maize genome. There are two homotranslocation series: proximal, interchanges proximal to wx, thus moving the wx locus to varied positions away from a centromere; and distal, interchanges distal to wx, thereby lengthening the segment distal to wx. 1. Among the controls (homoalleles on standard chromosomes), derived from outcrosses (heterozygous sources), yield more recombination than these combinations in inbred lines. 2. All heteroallelic, homotranslocation combinations, irrespective of the extent of the locus-centromere distance, are equal or less in recombination frequency than the wx recombination in the standard chromosome. 3. Among all heteroalleles on homotranslocations, there is a positive linear correlation of inter-allelic recombination with increasing distance from a centromere but the value is always less than found in the standard chromosomes. This also is true for the same heteroallele at different positions; the longer distances show a higher recombination value than the shorter wx-centromere distance. 4. There is no effect of a lengthening distal segment on wx interallelic recombination. 5. The frequencies of Wx pollen grains arising from homoalleles on homotranslocations in most instances (except for 90/90) are not significantly different from the frequencies found with standard chromosomes. 6. The reversion frequency of the same homoallele at different positions has no relationship with the wx-centromere or wx-breakage-point distance. 7. Different homoalleles at the same position are not equally affected in wx reversion rate at the new position, although no trend is evident in wx-centromere or wx-breakage-point distance. 8. The most variation in percentage change of the Wx frequency from the controls among different heteroalleles with the same homotranslocation is found among interchanges with relatively short wx-breakage-point distances. 9. There is a significant environmental effect; the greatest change between years is among the heteroalleles with higher wx recombination. 10. Homoalleles differ from heteroalleles in response to various factors, such as wx-centromere and wx-breakage-point distances. This supports the expectation that Wx pollen grains arising from homoalleles have a different origin than do Wx pollen grains arising from heteroalleles.
染色体易位被用来重新定位 wx 基因座的四个等位基因，以分析玉米基因组的重组潜力分布。有两个同异位系列：近端易位，交换 wx 近端，从而将 wx 基因座移动到远离着丝粒的不同位置；和远端易位，交换 wx 远端，从而延长 wx 远端的片段。1. 在对照（标准染色体上的同等位基因）中，来自杂交（杂合来源）的衍生，比自交系中的这些组合产生更多的重组。2. 所有异等位基因的同异位组合，无论其与着丝粒的距离如何，其重组频率都与标准染色体中的 wx 重组相等或更低。3. 在所有同异位上的异等位基因中，等位基因间重组与离着丝粒的距离呈正线性相关，但该值始终小于标准染色体中的值。对于同一异位的不同位置也是如此；较长的距离显示出比较短的 wx-着丝粒距离更高的重组值。4. 远端片段的延长对 wx 等位基因间重组没有影响。5. 在大多数情况下（除了 90/90 之外），同异位上的同等位基因产生的 Wx 花粉粒的频率与标准染色体中的频率没有显著差异。6. 不同位置的同一同等位基因的回复频率与 wx-着丝粒或 wx-断裂点距离无关。7. 同一位置的不同同等位基因在新位置的 wx 回复率上没有受到同等影响，尽管在 wx-着丝粒或 wx-断裂点距离上没有明显的趋势。8. 在不同的异等位基因中，同一位点的同一位点的同一位点在 wx 回复率上的变化百分比在 wx 断裂点距离相对较短的易位中变化最大。9. 不同异等位基因之间的 Wx 频率变化百分比在不同年份之间存在显著的环境效应；变化最大的是 wx 重组较高的异等位基因。10. 同等位基因与异等位基因在 wx-着丝粒和 wx-断裂点距离等各种因素的反应不同。这支持了这样的期望，即来自同等位基因的 Wx 花粉粒与来自异等位基因的 Wx 花粉粒的起源不同。
