Characterization of the polymorphism detected for the granule‐bound starch synthase ( WX gene) in wild einkorn wheat

BACKGROUND The WX gene encodes the granule‐bound starch synthase I or waxy protein, which is the sole enzyme responsible for amylose synthesis in wheat seeds. Wild einkorn wheat ( Triticum monococcum L. ssp. aegilopoides Link em. Thell.) could be an important source of variation for this gene. RESULTS This study assessed the WX gene variability in 14 accessions representative of the variation for waxy proteins detected in a collection of 170 accessions and compared their nucleotide sequences with the Wx‐A1a allele of common wheat (cv. Chinese Spring). Thirteen different alleles were found in this species, of which 11 were novel ( Wx‐A m 1c to Wx‐A m 1m ). A comparison between the deduced proteins from the novel alleles and the Wx‐A1a protein showed that there were up to 35 amino acid changes in both the transit peptide and the mature protein; some of them exhibited deleterious effects on the enzymatic function of these proteins. CONCLUSION The results obtained in the present study show that this species could be a potential source of new waxy variants.