Gardiner K
Eleanor Roosevelt Institute, Denver, CO 80206-1210, USA.
Trends Genet. 1996 Dec;12(12):519-24. doi: 10.1016/s0168-9525(97)81400-x.
Recent success in developing transcriptional maps of large genomic regions provide excellent opportunities for the investigation of mammalian genome organization. Detailed definition of organizational features will, in the short term, aid in prioritizing genomic sequencing efforts and in interpreting sequencing results and, in the long term, will surely provide insights into the structural, functional and evolutionary basis for the mammalian chromosome and chromosomal banding patterns. For such efforts, human chromosome 21 provides an excellent model system because the physical and clone maps are detailed, and several transcriptional mapping projects have provided large numbers of novel genes. It is, therefore, valuable at this point to examine these transcriptional mapping data and to compare them with the isochore model of the mammalian genome, which describes patterns in base composition and predicts gene distributions. Not only do compelling organizational patterns appear, but new questions about additional possible patterns in gene size, structure, conservation and transcription can be asked.
近期在绘制大型基因组区域转录图谱方面取得的成功为研究哺乳动物基因组组织提供了绝佳机会。在短期内，对组织特征的详细定义将有助于确定基因组测序工作的优先级并解释测序结果，而从长远来看，必将为哺乳动物染色体及染色体带型的结构、功能和进化基础提供见解。对于此类研究，人类21号染色体提供了一个出色的模型系统，因为其物理图谱和克隆图谱都很详细，并且多个转录图谱项目已提供了大量新基因。因此，此时检查这些转录图谱数据并将其与哺乳动物基因组的等容线模型进行比较很有价值，该模型描述了碱基组成模式并预测了基因分布。不仅出现了引人注目的组织模式，还可以提出有关基因大小、结构、保守性和转录方面其他可能模式的新问题。
