SGER: Alu Repeats in Higher Primates

在人类和其他灵长类物种的基因组(染色体)中，估计有500,000个Alu重复的DNA元素。大多数重复序列出现在进化的过去(大约1000万到2000万年前)，其他重复序列仍然出现在新的基因组位置；因此，它们的总数不断增加。了解这些Alu元素的传播方式是很重要的。这项建议的目的是确定Alu重复在我们的基因组中是否固定或瞬时(多态)，以及在多大程度上；它们是以可逆或不可逆的机制出现的。多态使有意义的变化和无意义的变化之间的区别变得模糊，从而使遗传分析变得非常复杂。一个角色的固定或多态状态是不可能预测的，它必须通过分析大量的个体来确定。如果Alu重复传播的模式能够被建立为不可逆转的，Alu可以被视为我们基因组进化动态中的坚实里程碑，并将成为系统发育分析的宝贵工具。

There are an estimated 500,000 Alu repetitive DNA elements in the genome (chromosomes) of humans and other primate species. Most of the repeats have arisen in the evolutionary past (some 10 to 20 million years ago), others are still arising at new genomic sites; thus their total number keeps increasing. It is important to understand the mode of spreading of these Alu elements. The objective of this proposal is to establish if, and to what extent, Alu repeats are fixed or transient (polymorphic) in our genome; whether they arise in reversible or irreversible mechanisms. Polymorphism greatly complicates genetic analyses by blurring the distinction between meaningful and meaningless changes. The fixed or polymorphic state of a character is impossible to predict, it has to be established by analyzing large numbers of individuals. If the mode by which Alu repeats spread can be established as being irreversible, Alu's can be viewed as solid landmarks in the evolutionary dynamics of our genome and will become invaluable tools for phylogenetic analyses.