Meta-Analysis of Genetic Factors for Potato Starch Phosphorylation

Abstract

Starch is one of the most demanded renewable feedstock in the world. The degree of phosphorylation of native potato (Solanum tuberosum L.) starch is a practically important quantitative trait, significantly influencing its physical and chemical properties. In this study, we evaluated the genetic diversity of the population of potato varieties and quantified phosphorus content in potato tuber starch harvested in 2017, 2018, and 2019. With the statistical methods, the most promising varieties for the next generation of breeding were identified for the first time. Genotyping and chemotyping data were utilized for genome-wide associations study (GWAS) in order to reveal genetic factors underlying the trait. GWAS based on a general linear model (GLM) with principal component analysis (PCA) was performed. The approach allowed us to identify two new, and confirm two previously found, significant SNPs on chromosome 5 associated with phosphorus content in starch. A search for the protein products coded in the genome regions carrying the significant SNPs revealed a cluster of genes that code glycoside and protein kinases, thus forming an operon-like structure. The genetic markers can be used for marker-assisted selection or to be considered as potential targets for genome editing to improve the industrially important properties of potato native starch via “intravital modification”.