Three water-soluble wheat endosperm proteins of the wheat variety Chinese Spring have been shown, by isoelectric focusing, to be the products of genes located on the long arms of chromosomes 7A, 7B and 7D. In the absence of any evidence of function these genes have been assigned the temporary symbol, Wsp-1.
Considerable intervarietal variation was found among a sample of 44 hexaploid wheat varieties. Five alleles at Wsp-A1, three at Wsp-B1 and two at Wsp-D1 were identified. Intrachromosomal mapping showed that Wsp-B1 is located distally on the long arm of chromosome 7B.
Alien homoeoloci were identified on chromosomes 7Hch of Hordeum chilense, 7H of H. vulgare, 7E of Agropyron elongatum, 7S1 of Aegilops sharonensis and 7V of Dasypyrum villosum. Some other loci encoding WSPs found in wheat and some alien species are also briefly described.