Department of Biology, Pennsylvania State University, University Park, PA 16802, USA.
Department of Computer Science and Engineering, and Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, PA 16802, USA; Genome Sciences Institute and Center for Medical Genomics, Huck Institutes of the Life Sciences, Pennsylvania State University, University Park, PA 16802, USA.
Trends Genet. 2017 Apr;33(4):266-282. doi: 10.1016/j.tig.2017.01.008. Epub 2017 Feb 22.
Hundreds of vertebrate genomes have been sequenced and assembled to date. However, most sequencing projects have ignored the sex chromosomes unique to the heterogametic sex - Y and W - that are known as sex-limited chromosomes (SLCs). Indeed, haploid and repetitive Y chromosomes in species with male heterogamety (XY), and W chromosomes in species with female heterogamety (ZW), are difficult to sequence and assemble. Nevertheless, obtaining their sequences is important for understanding the intricacies of vertebrate genome function and evolution. Recent progress has been made towards the adaptation of next-generation sequencing (NGS) techniques to deciphering SLC sequences. We review here currently available methodology and results with regard to SLC sequencing and assembly. We focus on vertebrates, but bring in some examples from other taxa.
迄今为止,已有数百个脊椎动物基因组被测序和组装。然而,大多数测序项目都忽略了性染色体,这些性染色体是异配子性(XY)所特有的 Y 和 W 染色体,也被称为性限染色体(SLCs)。事实上,具有雄性异配子性(XY)的物种中的单体和重复 Y 染色体,以及具有雌性异配子性(ZW)的物种中的 W 染色体,都很难进行测序和组装。然而,获得它们的序列对于理解脊椎动物基因组功能和进化的复杂性非常重要。最近,下一代测序(NGS)技术在破译 SLC 序列方面取得了进展。我们在这里回顾了目前可用的 SLC 测序和组装方法和结果。我们专注于脊椎动物,但也引入了一些来自其他分类群的例子。