背景回顾：As a perennial crop, oil-Camellia possesses a long domestication history and produces high-quality seed oil that is beneficial to human health. Camellia oleifera Abel. is a sister species to the tea plant, which is extensively cultivated for edible oil production. 

提出问题：However, the molecular mechanism of the domestication of oil-Camellia is still limited due to the lack of sufficient genomic information. 

主要研究：To elucidate the genetic and genomic basis of evolution and domestication, here we report a chromosome-scale reference genome of wild oil-Camellia (2.95 Gb), together with transcriptome sequencing data of 221 cultivars. 

结果1-组装和注释：The oil-Camellia genome, assembled by an integrative approach of multiple sequencing technologies, consists of a large proportion of repetitive elements (76.1%) and high heterozygosity (2.52%). 

结果2-遗传图谱：We construct a genetic map of high-density corrected markers by sequencing the controlled-pollination hybrids. 

结果3-GWAS：Genome-wide association studies reveal a subset of artificially selected genes that are involved in the oil biosynthesis and phytohormone pathways. 

结果4-优异等位基因：Particularly, we identify the elite alleles of genes encoding sugar-dependent triacylglycerol lipase 1, β-ketoacyl-acyl carrier protein synthase III, and stearoyl-acyl carrier protein desaturases; these alleles play important roles in enhancing the yield and quality of seed oil during oil-Camellia domestication. 

结论：We generate a chromosome-scale reference genome for oil-Camellia plants and demonstrate that the artificial selection of elite alleles of genes involved in oil biosynthesis contributes to oil-Camellia domestication.

 摘 要 

油茶作为一种多年生作物，具有非常悠久的驯化历史，能够产出对人类健康有益的优质籽油。油茶（Camellia oleifera ），是茶树的姊妹种，因其可用于生产可食用性油而被广泛种植。然而，由于缺乏足够的基因组信息，目前对于油茶驯化分子机制的了解仍然有限。为了阐明油茶演化和驯化的遗传和基因组基础，作者报道了野生油茶2.95 Gb的染色体级别参考基因组，同时对221个栽培个体进行了转录组测序。作者基于多种测序技术的测序数据组装获得了油茶的基因组，重复序列占基因组的76.1%，杂合度高达2.52%。作者通过对控制授粉的杂种群体进行测序并获得分子标记，构建了高密度的遗传图谱。全基因组关联分析解释了一系列受到人工选择的基因，这些基因多是参与油的生物合成和植物激素通路。尤其是，作者鉴定到了编码糖依赖性三酰甘油脂肪酶（SDP1）、Ⅲ型β-酮酰基-酰基载体蛋白合酶（KAS III）以及硬脂酰-酰基载体蛋白去饱和酶（SADs）的等位基因，这些基因在油茶驯化过程中增强籽油产量和质量方面存在重要作用。综上，本文的研究所报道的油茶参考基因组揭示了对参与油生物合成基因的优异等位基因的人工选择作用于油茶的驯化。