Mammalian L1 retrotransposons as genetic characters

这个项目的最初推动力是哺乳动物的L1元件是基因组内的专性寄生虫，通过将其RNA转录本复制到基因组DNA中进行复制。至少在过去的1亿年里，它们一直在哺乳动物谱系中生活和进化，在此期间，至少出现了16个连续的L1家族，但在被一个新的活跃家族取代后灭绝，这一家族存在于现代人类中。已灭绝的L1家族的DNA插入片段仍留在基因组中，在那里它们以中性突变率积累突变。这些插入代表了无与伦比的DNA化石来源，这些化石提供了宿主的基因记录，我们对这些记录的分析表明，DNA修复可能是突变的。我们早些时候已经证明了这一点，并确定了修复诱导突变的几种机制。然而，由于我们在本评级年度没有投入任何资源，因此我们没有什么新的情况要报告。

The original impetus for this project was that mammalian L1 elements are obligate intra-genomic parasites that replicate by copying their RNA transcripts into genomic DNA. They have been residing and evolving in mammalian lineages for at least the last 100 million years, during which time at least 16 successive L1 families arose, only to go extinct having been supplanted by a novel active family, which is present in modern humans. The DNA inserts of the extinct L1 families remain in the genome where they accumulate mutations at the neutral mutation rate. These insertions represent an unparalleled source of DNA fossils that provide a genetic record of its host and our analysis of which suggested that DNA repair may be mutagenic. We had earlier demonstrated that this is indeed the case and determined several mechanisms of repair-induced mutagenesis. However, as we devoted no resources this project in the current rating year we have nothin new to report.