McClure Kendra A, Gong YuiHui, Song Jun, Vinqvist-Tymchuk Melinda, Campbell Palmer Leslie, Fan Lihua, Burgher-MacLellan Karen, Zhang ZhaoQi, Celton Jean-Marc, Forney Charles F, Migicovsky Zoë, Myles Sean
1Department of Plant and Animal Sciences, Faculty of Agriculture, Dalhousie University, Truro, NS B2N 5E3 Canada.
Agriculture and Agri-Food Canada, Kentville Research and Development Centre, Kentville, NS B4N 1J5 Canada.
Hortic Res. 2019 Sep 7;6:107. doi: 10.1038/s41438-019-0190-y. eCollection 2019.
Apples are a nutritious food source with significant amounts of polyphenols that contribute to human health and wellbeing, primarily as dietary antioxidants. Although numerous pre- and post-harvest factors can affect the composition of polyphenols in apples, genetics is presumed to play a major role because polyphenol concentration varies dramatically among apple cultivars. Here we investigated the genetic architecture of apple polyphenols by combining high performance liquid chromatography (HPLC) data with ~100,000 single nucleotide polymorphisms (SNPs) from two diverse apple populations. We found that polyphenols can vary in concentration by up to two orders of magnitude across cultivars, and that this dramatic variation was often predictable using genetic markers and frequently controlled by a small number of large effect genetic loci. Using GWAS, we identified candidate genes for the production of quercitrin, epicatechin, catechin, chlorogenic acid, 4--caffeoylquinic acid and procyanidins B1, B2, and C1. Our observation that a relatively simple genetic architecture underlies the dramatic variation of key polyphenols in apples suggests that breeders may be able to improve the nutritional value of apples through marker-assisted breeding or gene editing.
苹果是一种营养丰富的食物来源，含有大量对人类健康有益的多酚类物质，主要作为膳食抗氧化剂。尽管许多采前和采后因素会影响苹果中多酚类物质的组成，但由于苹果品种间多酚浓度差异很大，因此推测遗传因素起着主要作用。在这里，我们通过将高效液相色谱（HPLC）数据与来自两个不同苹果群体的约10万个单核苷酸多态性（SNP）相结合，研究了苹果多酚的遗传结构。我们发现，不同品种的苹果中多酚浓度差异可达两个数量级，而且这种显著差异通常可以通过遗传标记预测，并且常常由少数几个具有大效应的遗传位点控制。通过全基因组关联研究（GWAS），我们确定了用于生产槲皮苷、表儿茶素、儿茶素、绿原酸、4-咖啡酰奎尼酸和原花青素B1、B2和C1的候选基因。我们观察到，相对简单的遗传结构是苹果中关键多酚显著差异的基础，这表明育种者或许能够通过标记辅助育种或基因编辑来提高苹果的营养价值。
