背景回顾：Potato (Solanum tuberosum L.) originated in the Andes and evolved its vegetative propagation strategy through short day-dependent tuber development. 

主要研究：Herein, we present a high-quality, chromosome-scale reference genome sequence of a tetraploid potato cultivar. 

结果1-基因组基本信息：The total length of this genome assembly was 2.67 Gb, with scaffold N50 and contig N50 sizes of 46.24 and 2.19 Mb, respectively. In total, 1.69 Gb repetitive sequences were obtained through de novo annotation, and long terminal repeats were the main transposable elements. A total of 126,070 protein-coding genes were annotated, of which 125,077 (99.21%) were located on chromosomes. 

结果2-同源基因：The 48 chromosomes were classified into four haplotypes. We annotated 31,506 homologous genes, including 5,913 (18.77%) genes with four homologs, 11,103 (35.24%) with three homologs, 12,177 (38.65%) with two homologs, and 2,313 (7.34%) with one homolog. 

结果3-基因扩张：MLH3, MSH6/7 and RFC3, which are the genes involved in the mismatch repair pathway, were found to be significantly expanded in the tetraploid potato genome relative to the diploid potato genome. 

结果4-GWAS：Genome-wide association analysis revealed that cytochrome P450, flavonoid synthesis, chalcone enzyme, glycosyl hydrolase and glycosyl transferase genes were significantly correlated with the flesh colors of potato tuber in 150 tetraploid potatoes.  

结论：This study provides valuable insights into the highly heterozygous autotetraploid potato genome and may facilitate the development of tools for potato cultivar breeding and further studies on autotetraploid crops.

 摘 要 

马铃薯起源于安第斯山脉，通过短日照依赖性的块茎发育演化出通过营养器官进行繁殖的策略。本文中，作者报道了一个四倍体马铃薯栽培种的高质量、染色体级别参考基因组。该基因组的大小为2.67Gb，scaffold N50长46.24Mb，contig N50长2.19Mb。通过从头预测的方法，共注释出了1.69Gb的重复序列，其中长末端重复（LTR）是最主要的转座子。作者一共鉴定了126070个蛋白编码基因，其中99.21%的基因位于染色体上。48个染色体可以进一步划分为四套单倍型。通过这些不同单倍型染色体上基因的进一步划分，作者共鉴定了31506组同源基因，其中18.77%具有4个同源基因，35.24%具有3个同源基因，38.65%具有2个同源基因，剩余的7.34%仅具有一个同源基因。MLH3、MSH6/7和RFC3基因参与错配修复途径，相比于二倍体，这些基因在四倍体马铃薯的基因组中发生了显著的扩张。通过对150份四倍体马铃薯材料的全基因组关联分析，发现细胞色素P450、类黄酮合成、查尔酮酶、糖基水解酶以及糖基转移酶显著与块茎的果肉颜色相关。本文的研究结果报道了一个高度杂合的同源四倍体马铃薯参考基因组，为未来的马铃薯栽培种育种以及同源四倍体作物的研究提供了遗传资源和参考。