基因复制是产生新基因和引发基因组革新的一种重要机制。转位子介导的序列转换（Retrotransposon-mediated sequence transduction，生物通编者译，如转位子在运动过程中会携带其侧翼序列（flanking sequence））是一种已经被认可的基因复制机制。
L1 exon（外显子）重排（shuffling ）潜能曾经在细胞培植测试（cell culture assays）中有过报道，而且在培养细胞的基因组中也鉴别出两种潜在的L1介导的外显子重排事件。SVA是灵长类一种年轻的转位子家族，并且其3’侧翼序列在转位过程中能够进行转换。
最近，路易斯安娜州立大学BioModular Multi-Scale Systems中心研究员邢锦川（Jinchuan Xing，音译）、王慧（Hui Wang，音译）对人类基因组中全部的全长SVA元件进行了检测，评估SVA介导的3’端序列转换的频率和影响。研究详细结果刊登于11月21日电子版PNAS。
结果显示，约有53kb的基因组序列是由143种不同的SVA介导的转换事件复制得到的。特别是，在人类和非洲人猿（African great apes）分道扬镳以前，一组SVA元件通过SVA介导的转换事件，将整个AMAC基因在人类基因组中复制了三次。作为对原始AMAC基因的补充，三次转换的AMAC拷贝包含了完整的ORF（开放阅读框），至少有两个在不同的人类组织中转录活跃。新复制的整个基因和通过转位介导的序列转换产生先前未曾描述过的基因家族，代表了可移动元件影响宿主基因组的一种重要的机制。
英文原文：
Emergence of primate genes by retrotransposon-mediated sequence transduction
Department of Biological Sciences, Biological Computation and Visualization Center, Center for BioModular Multi-Scale Systems, Louisiana State University, 202 Life Sciences Building, Baton Rouge, LA 70803; and Tulane Cancer Center SL-66, Department of Environmental Health Sciences, Tulane University Health Sciences Center, New Orleans, LA 70112
Edited by Susan R. Wessler, University of Georgia, Athens, GA, and approved June 28, 2006 (received for review April 20, 2006)
Gene duplication is one of the most important mechanisms for creating new genes and generating genomic novelty. Retrotransposon-mediated sequence transduction (i.e., the process by which a retrotransposon carries flanking sequence during its mobilization) has been proposed as a gene duplication mechanism. L1 exon shuffling potential has been reported in cell culture assays, and two potential L1-mediated exon shuffling events have been identified in the genome. SVA is the youngest retrotransposon family in primates and is capable of 3' flanking sequence transduction during retrotransposition. In this study, we examined all of the full-length SVA elements in the human genome to assess the frequency and impact of SVA-mediated 3' sequence transduction. Our results showed that 53 kb of genomic sequences have been duplicated by 143 different SVA-mediated transduction events. In particular, we identified one group of SVA elements that duplicated the entire AMAC gene three times in the human genome through SVA-mediated transduction events, which happened before the divergence of humans and African great apes. In addition to the original AMAC gene, the three transduced AMAC copies contain intact ORFs in the human genome, and at least two are actively transcribed in different human tissues. The duplication of entire genes and the creation of previously undescribed gene families through retrotransposon-mediated sequence transduction represent an important mechanism by which mobile elements impact their host genomes.
