the polymorphism of waxya1 and waxyb1 gene and their mutation effects on the structure of gbss1 protein in some iranian wheat

gbss protein, that is the product of waxy gene (wx) is one of the major enzyme in starch biosynthesis that controls the proportion of amylose to amylopechtine and its absence leads to production of starch with low amylose and higher amylopechtine content, called waxy starch.wx-a1, wx-b1, wx-d1 are three locuses in bread wheat (triticum aestivum) genome that encodes gbss protein and waxy starch is produced when all of them are null. in this project the polymorphism of wx-a1 and wx-b1 genes in 20 tetraploid and hexaploid iranian wheat cultivars was studied by pcr-rflp and direct sequencing techniques. result showed any polymorphism in wx-b1 genes of studied population but pcr-rflp demonstrated the polymorphism in the second part of wx-a1 gene of hamoun and alvand cultivars. according to sequencing and in silico studies of the mutation effects on gbss features, the two selected cultivars can be assumed as a donor for wx-a1 null allele.