Morgan Andrew P
Department of Medicine, University of North Carolina, Chapel Hill, NC 27514, USA.
bioRxiv. 2025 Aug 12:2025.08.10.669551. doi: 10.1101/2025.08.10.669551.
Meiotic recombination ensures the fidelity of chromosome segregation in most organisms with sexual reproduction. The distribution of crossovers along chromosomes is governed in part by interference, which prevents multiple crossovers from occurring in close proximity, though not all crossovers are subject to interference. Neither the factors that control strength of interference, nor the extent to which they vary within and between species, are well understood. Here we confirm that that crossover interference is stronger in male than in female meiosis in house mice (), provide the first estimate of the proportion of non-interfering crossovers in female mice, and show that this proportion is lower than in males. Interference is stronger on shorter chromosomes in both sexes, but the frequency of interference escape is similar across the range of chromosome size. Together with evidence that interference varies across strains and subspecies, our results provide a foundation for studying the evolution and sexual dimorphism in this important feature of meiosis in mice.
减数分裂重组确保了大多数有性生殖生物中染色体分离的准确性。交叉在染色体上的分布部分受干涉作用的控制，干涉可防止多个交叉在近距离内发生，不过并非所有交叉都受干涉影响。无论是控制干涉强度的因素，还是这些因素在物种内部和物种之间的变化程度，目前都还没有得到很好的理解。在这里，我们证实小家鼠雄性减数分裂中的交叉干涉比雌性更强，首次估计了雌性小鼠中不受干涉的交叉比例，并表明该比例低于雄性。在两性中，较短染色体上的干涉更强，但在整个染色体大小范围内，干涉逃脱的频率相似。结合干涉在不同品系和亚种间存在差异的证据，我们的研究结果为研究小鼠减数分裂这一重要特征的进化和性别二态性奠定了基础。
