A genetic test to determine the origin of maternal transmission ratio distortion. Meiotic drive at the mouse Om locus.
A genetic test to determine the origin of maternal transmission ratio distortion. Meiotic drive at the mouse Om locus.
复制标题
确定母体传播率扭曲根源的基因测试。
DOI：
10.1093/genetics/154.1.333
复制
发表时间：
2000
期刊：
影响因子：
3.3
通讯作者：
Sapienza,C
中科院分区：
文献类型：
--
作者：
Pardo-ManueldeVillena,F;delaCasa-Esperon,E;Briscoe,TL;Sapienza,C
我们以前已经证明，杂合雌性与C57BL/6雄性杂交的后代在小鼠11号染色体上的Om位点上表现出传输率畸变。这个结果在几个独立的实验中得到了重复。在这里，我们展示了扭曲映射到11号染色体上的单个位点，与Om密切相关，并且基因转换与这种现象的起源无关。为了进一步研究传动比畸变的起源，我们利用众所周知的重组对母体减数分裂驱动的影响进行了测试。本文提出的基因检测是基于对同一染色体上扭曲位点和着丝粒的基因型分析，来区分减数分裂过程中等位基因的不平等分离和致死性。我们使用这个测试来确定在Om轨迹观察到的传动比失真的原因。我们的结果表明，在第二次减数分裂时，传输率畸变是由于等位基因在极体上的不均匀分离造成的。由于染色体分离畸变的存在也取决于父亲的基因型，因此我们的研究结果证实，精子可以影响母亲染色体向第二极体的分离。
We have shown previously that the progeny of crosses between heterozygous females and C57BL/6 males show transmission ratio distortion at the Om locus on mouse chromosome 11. This result has been replicated in several independent experiments. Here we show that the distortion maps to a single locus on chromosome 11, closely linked to Om, and that gene conversion is not implicated in the origin of this phenomenon. To further investigate the origin of the transmission ratio distortion we generated a test using the well-known effect of recombination on maternal meiotic drive. The genetic test presented here discriminates between unequal segregation of alleles during meiosis and lethality, based on the analysis of genotype at both the distorted locus and the centromere of the same chromosome. We used this test to determine the cause of the transmission ratio distortion observed at the Om locus. Our results indicate that transmission ratio distortion at Om is due to unequal segregation of alleles to the polar body at the second meiotic division. Because the presence of segregation distortion at Om also depends on the genotype of the sire, our results confirm that the sperm can influence segregation of maternal chromosomes to the second polar body.