Allelic Variation of High-Molecular-Weight Glutenin Genes in Triticum Species and Triticale (× Triticosecale Wittmack)

High-molecular-weight glutenin subunits (HMW-GS) encoded by alleles at the Glu-A1, Glu-B1, and Glu-D1 loci confer unique bread-making properties of common wheat (Triticum aestivum L.). The identification of HMW-GS is the prerequisite for pyramiding high-quality glutenin genes. The present review is designed to list all published HMW-GS alleles in Triticum species and triticale (A- and B genomes), focusing on methods for their identification. T. monococcum is characterized by 37 alleles at the Glu-1 locus versus four alleles in T. thaoudar and 39 in T. urartu. In total, 80 alleles at Glu-A1 of diploid Triticum species and about 42 alleles found in polyploid wheat landraces and varieties (4x and 6x), including triticale, were listed. Allelic variation at the Glu-B1 locus is divided into 3 groups: a – z, aa – az, and ba – ct, comprising 121 alleles, of which 26 subunits have unspecified alleles. At least 51 allelic variants at locus Glu-D1 of Triticum species were indicated, along with carriers of the species level. In addition, subunit-specific genetic loci have been tagged, facilitating molecular marker development of high-gluten wheat cultivars through marker-assisted breeding.