Plant Gene Resources of Canada, Saskatoon Research and Development Centre, Agriculture and Agri-Food Canada, 107 Science Place, Saskatoon, SK S7N 0X2, Canada.
Int J Mol Sci. 2024 May 29;25(11):5930. doi: 10.3390/ijms25115930.
Long-term conservation of more than 7 million plant germplasm accessions in 1750 genebanks worldwide is a challenging mission. The extent of deleterious mutations present in conserved germplasm and the genetic risk associated with accumulative mutations are largely unknown. This study took advantage of published barley genomic data to predict sample-wise mutation burdens for 19,778 domesticated barley ( L.) accessions conserved ex situ. It was found that the conserved germplasm harbored 407 deleterious mutations and 337 (or 82%) identified deleterious alleles were present in 20 (or 0.1%) or fewer barley accessions. Analysis of the predicted mutation burdens revealed significant differences in mutation burden for several groups of barley germplasm (landrace > cultivar (or higher burden estimate in landrace than in cultivar); winter barley > spring barley; six-rowed barley > two-rowed barley; and 1000-accession core collection > non-core germplasm). Significant differences in burden estimate were also found among seven major geographical regions. The sample-wise predicted mutation burdens were positively correlated with the estimates of sample average pairwise genetic difference. These findings are significant for barley germplasm management and utilization and for a better understanding of the genetic risk in conserved plant germplasm.
长期保存全球 1750 个基因库中的超过 700 万份植物种质资源是一项极具挑战性的任务。受保护的种质资源中存在的有害突变的程度以及累积突变带来的遗传风险在很大程度上是未知的。本研究利用已发表的大麦基因组数据，预测了 19778 份已在原地保存的驯化大麦（ Hordeum vulgare L.）资源的个体突变负担。研究发现，受保护的种质资源中含有 407 个有害突变，其中 337 个（或 82%）已鉴定的有害等位基因存在于 20 个（或 0.1%）或更少的大麦资源中。对预测的突变负担的分析表明，几个大麦种质群体的突变负担存在显著差异（地方品种＞栽培品种（或地方品种的负担估计高于栽培品种）；冬大麦＞春大麦；六棱大麦＞二棱大麦；1000 份核心种质库＞非核心种质）。七个主要地理区域之间的负担估计也存在显著差异。个体预测的突变负担与样本平均成对遗传差异的估计呈正相关。这些发现对于大麦种质资源的管理和利用以及更好地理解受保护植物种质资源中的遗传风险具有重要意义。
