Development of PCR-based markers for identification of wheat HMW glutenin Glu-1Bx and Glu-1By alleles

Background In common wheat ( Triticum aestivum L.), allelic variations in the high-molecular-weight glutenin subunits Glu - B1 locus have important effects on grain end-use quality. The Glu - B1 locus consists of two tightly linked genes encoding x- and y-type subunits that exhibit highly variable frequencies. However, studies on the discriminating markers of the alleles that have been reported are limited. Here, we developed 11 agarose gel-based PCR markers for detecting Glu - 1Bx and Glu - 1By alleles. Results By integrating the newly developed markers with previously published PCR markers, nine Glu - 1Bx locus alleles ( Glu - 1Bx6 , Glu - 1Bx7 , Glu - 1Bx7 *, Glu - 1Bx7 OE , Glu - 1Bx13 , Glu - 1Bx14 (−) , Glu - 1Bx14 (+) / Bx20 , and Glu - 1Bx17 ) and seven Glu-1By locus alleles ( Glu - 1By8 , Glu - 1By8 *, Glu - 1By9 , Glu - 1By15/By20 , Glu - 1By16 , and Glu - 1By18 ) were distinguished in 25 wheat cultivars. Glu - 1Bx6 , Glu - 1Bx13 , Glu - 1Bx14 (+) / Bx20 , Glu - 1By16 , and Glu - 1By1 8 were distinguished using the newly developed PCR markers. Additionally, the Glu - 1Bx13 and Glu - 1Bx14 (+) / Bx20 were distinguished by insertions and deletions in their promoter regions. The Glu - 1Bx6, Glu - 1Bx7, Glu - 1By9 , Glu - 1Bx14 (−) , and Glu - 1By15 / By20 alleles were distinguished by using insertions and deletions in the gene-coding region. Glu - 1By13 , Glu - 1By16 , and Glu - 1By18 were dominantly identified in the gene-coding region. We also developed a marker to distinguish between the two Glu - 1Bx14 alleles. However, the Glu - 1Bx14 (+) + Glu - 1By15 and Glu - 1Bx20 + Glu - 1By20 allele combinations could not be distinguished using PCR markers. The high-molecular-weight glutenin subunits of wheat varieties were analyzed by ultra-performance liquid chromatography and sodium dodecyl sulfate–polyacrylamide gel electrophoresis, and the findings were compared with the results of PCR analysis. Conclusions Seven Glu - 1Bx and four Glu - 1By allele detection markers were developed to detect nine Glu - 1Bx and seven Glu - 1By locus alleles, respectively. Integrating previously reported markers and 11 newly developed PCR markers improves allelic identification of the Glu - B1 locus and facilitates more effective analysis of Glu - B1 alleles molecular variations, which may improve the end-use quality of wheat.