African trypanosomes escape the mammalian immune response by antigenic variation-the periodic exchange of one surface coat protein, in Trypanosoma brucei the variant surface glycoprotein (VSG), for an immunologically distinct one. VSG transcription is monoallelic, with only one VSG being expressed at a time from a specialized locus, known as an expression site. VSG switching is a predominantly recombination-driven process that allows VSG sequences to be recombined into the active expression site either replacing the currently active VSG or generating a 'new' VSG by segmental gene conversion. In this review, we describe what is known about the factors that influence this process, focusing specifically on DNA repair and recombination.

中文翻译：

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通过非洲锥虫的DNA修复和重组来逃避免疫系统。

非洲锥虫通过抗原变异逃避了哺乳动物的免疫反应-在布鲁氏锥虫中，一种表面外壳蛋白（一种变体表面糖蛋白（VSG））周期性地交换为一种免疫学上独特的蛋白。VSG转录是单等位基因，一次只能从一个特定的位点（称为表达位点）表达一个VSG。VSG转换是一个主要由重组驱动的过程，该过程允许VSG序列重组为活性表达位点，从而取代当前的活性VSG或通过片段基因转换产生“新的” VSG。在这篇综述中，我们描述了影响该过程的因素的已知信息，特别是DNA修复和重组。