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The amylose content of wheat starch is regulated by granule-bound starch synthase I (GBSSI), otherwise known as the 'waxy' (Wx) protein. Due to its allohexaploid genome, wheat possesses three separate alleles that encode for the Wx protein, and contribute to amylose synthesis. The three Wx proteins of wheat are commonly referred to as Wx-A1, Wx-B1, Wx-D1 according to the chromosome locus. The identification of germplasms possessing null alleles for the various GBSSI genes has facilitated the production of recombinate inbred lines (RILs) with various waxy gene combinations and amylose contents. The ability to alter the amylose content of wheat will be beneficial for the production of many high quality foods including Udon-style noodles, which require flours with somewhat reduced amylose contents. The objective of this study was to identify the Wx alleles or combinations of alleles important for the production of Udon noodles. Kanto 107 (Wx-D1) and Bai Huo (Wx-A1, Wx-B1) were crossed to generate material possessing all possible Wx gene combinations. The resulting progeny were advanced by single-seed descent to produce the RILs. GBSSI alleles were characterized by SDS-PAGE for each line. Lines were then grouped according to the 'waxy' genotype and correlated to flour swelling volume and noodle texture analyses. Determining the relative effects that GBSSI loci have on starch properties and noodle texture will enable breeders to develop cultivars with superior end uses.