Mallon A M, Platzer M, Bate R, Gloeckner G, Botcherby M R, Nordsiek G, Strivens M A, Kioschis P, Dangel A, Cunningham D, Straw R N, Weston P, Gilbert M, Fernando S, Goodall K, Hunter G, Greystrong J S, Clarke D, Kimberley C, Goerdes M, Blechschmidt K, Rump A, Hinzmann B, Mundy C R, Miller W, Poustka A, Herman G E, Rhodes M, Denny P, Rosenthal A, Brown S D
MRC UK Mouse Genome Centre and Mammalian Genetics Unit, Harwell, Oxon, UK.
Genome Res. 2000 Jun;10(6):758-75. doi: 10.1101/gr.10.6.758.
The progress of human and mouse genome sequencing programs presages the possibility of systematic cross-species comparison of the two genomes as a powerful tool for gene and regulatory element identification. As the opportunities to perform comparative sequence analysis emerge, it is important to develop parameters for such analyses and to examine the outcomes of cross-species comparison. Our analysis used gene prediction and a database search of 430 kb of genomic sequence covering the Bpa/Str region of the mouse X chromosome, and 745 kb of genomic sequence from the homologous human X chromosome region. We identified 11 genes in mouse and 13 genes and two pseudogenes in human. In addition, we compared the mouse and human sequences using pairwise alignment and searches for evolutionary conserved regions (ECRs) exceeding a defined threshold of sequence identity. This approach aided the identification of at least four further putative conserved genes in the region. Comparative sequencing revealed that this region is a mosaic in evolutionary terms, with considerably more rearrangement between the two species than realized previously from comparative mapping studies. Surprisingly, this region showed an extremely high LINE and low SINE content, low G+C content, and yet a relatively high gene density, in contrast to the low gene density usually associated with such regions.
人类和小鼠基因组测序计划的进展预示着将两个基因组进行系统的跨物种比较作为一种识别基因和调控元件的强大工具的可能性。随着进行比较序列分析机会的出现，制定此类分析的参数并研究跨物种比较的结果非常重要。我们的分析使用了基因预测以及对覆盖小鼠X染色体Bpa/Str区域的430 kb基因组序列和来自同源人类X染色体区域的745 kb基因组序列进行数据库搜索。我们在小鼠中鉴定出11个基因，在人类中鉴定出13个基因和两个假基因。此外，我们使用成对比对和搜索超过定义序列同一性阈值的进化保守区域（ECR）来比较小鼠和人类序列。这种方法有助于在该区域鉴定出至少另外四个假定的保守基因。比较测序表明，从进化角度来看，该区域是一个镶嵌体，两个物种之间的重排比之前从比较图谱研究中认识到的要多得多。令人惊讶的是，与通常与此类区域相关的低基因密度相反，该区域显示出极高的长散在核元件（LINE）含量和低短散在核元件（SINE）含量、低G+C含量，但基因密度相对较高。
