背景回顾：Tea is an important global beverage crop and is largely clonally propagated. 

提出问题：Despite previous studies on the species, its genetic and evolutionary history deserves further research.

主要研究：Here, we present a haplotype-resolved assembly of an Oolong tea cultivar, Tieguanyin. 

结果1-等位基因特异性表达：Analysis of allele-specific expression suggests a potential mechanism in response to mutation load during long-term clonal propagation. 

结果2-群体基因组：Population genomic analysis using 190 Camellia accessions uncovered independent evolutionary histories and parallel domestication in two widely cultivated varieties, var. sinensis and var. assamica. It also revealed extensive intra- and interspecific introgressions contributing to genetic diversity in modern cultivars. 

结果3-选择分析：Strong signatures of selection were associated with biosynthetic and metabolic pathways that contribute to flavor characteristics as well as genes likely involved in the Green Revolution in the tea industry. 

结论：Our results offer genetic and molecular insights into the evolutionary history of Camellia sinensis and provide genomic resources to further facilitate gene editing to enhance desirable traits in tea crops.

 摘 要 

茶树是全球重要的饮料作物，大部分通过无性繁殖。尽管对于茶树的研究已经历来已久，但其遗传和演化历史值得进一步研究。本文中，作者解析了一个乌龙茶品种，即铁观音的单倍型级别基因组。对于等位基因特异性表达的分析揭示了一个长期无性繁殖过程中，响应突变负荷的潜在机制。基于190份茶树种质，作者进行了群体基因组分析，揭示了两个广为栽培的茶树品种（即茶和普洱茶）的独立演化历史和平行的驯化过程。该群体数据还揭示了广泛的种内和种间遗传滲入有助于现代品种的遗传多样性。另外，作者发现强烈的选择信号与茶树风味相关物质的生物合成和代谢途径有关，以及与那些可能参与茶产业绿色革命的基因相关。本文的研究结果为茶树的演化历史提供了遗传和分子层面的视野，并为进一步加速基因编辑以改良茶树作物的目标性状提供了基因组资源。