Two partial cDNA clones, pc hor1-3 and pc-919, encoding the carboxyterminal portion of two different C-hordein polypeptides have been sequenced. pc hor1-3 can be translated into a frame of 74 amino acids, part of which is identical to the amino acid sequence of a C-hordein chymotryptic peptide. The 3′ non-coding region is 174 nucleotides in length and extends to the polyadenylation site. The region has two putative polyadenylation signals, AATAAA, located 27 and 80 nucleotides upstream from the poly(A)-tail. Three RNA species, 1800, 2100 and 4300 bases in length, can be detected in the endosperm using pc hor1-3 as probe. These could code for C-hordein polypeptides of 48, 67 and 144 kD, respectively. Hybridization of pc hor1-3 to restriction endonuclease fragments of nuclear barley DNA suggests that 6-8 genes code for the C-hordein polypeptides. The nucleotide sequence of the second cDNA clone, pc-919, can be translated into 64 amino acids, of which the 22 carboxyterminal amino acid residues are identical to the carboxyterminal reading frame encoded by pc hor1-3. The adjacent 42 amino acid long reading frame shows homology to that deduced from pc hor1-3, but the nucleotide sequence is different and highly homologous to the 5′ coding sequence found in a B-hordein genomic clone. Hybridization using this part of pc-919 as a probe detects RNAs of 1200 and 1400 bases only. Thus pc-919 represents a gene containing sequences related to both Hor1 and the Hor2 locus, and is the first nucleotide sequence data giving evidence that the two loci are related.