Using Y chromosome haplotype diversity to test for selection within and between natural populations of the plant Silene latifolia.

本研究拟结合不同种类、不同突变时间尺度的序列差异数据，以及变异的地理分布信息，以检验自然选择是否影响了不同y染色体的频率。我们建议通过分离新的y连锁基因，并在多个野生欧洲群体的植物中重新测序，从而根据低突变率变异定义单倍型，并使用高突变率变异（微卫星）更详细地研究单倍型的年龄。这可以表明某些Y染色体基因型是局部适应的，还是在不同人群中具有优势。除了提供关于选择对Y染色体影响的有趣数据外，该结果将使我们能够测试选择引起的局部适应是否可以解释这些物种中Y染色体变异倾向于居中频率的令人困惑的观察结果，以及这种适应是否导致Y连锁变异的多样性低于x连锁同源变异。

This proposal is to combine data on sequence differences of various kinds, with different mutational time-scales, and information on the geographical distributions of variants, in order to test whether selection is affecting the frequencies of different Y-chromosomes in Silene latifolia and S. dioica. We propose to do this by isolating new Y-linked genes, and resequencing them in plants from multiple wild European populations, so as to define haplotypes based on low mutation rate variants, and to study the ages of the haplotypes in finer detail using higher mutation rate variants (microsatellites). This can indicate whether certain Y chromosome genotypes are locally adapted, or are advantageous across different populations. As well as providing interesting data on the effects of selection on Y chromosomes, the results will allow us to test whether selection causing local adaptation can explain the puzzling observation that Y chromosome variants in these species tend to be at intermediate frequencies, and whether such adaptation contributes to lower diversity of Y-linked variants, compared with variants in the X-linked homologues.