The gliadins from 16 wheat varieties were separated by reversed-phase high-performance liquid chromatography on octadecyl silica gel into about ten major and numerous minor components. Preliminary separation of gliadins by gel permeation high-performance liquid chromatography was shown to be unnecessary. The varieties differed significantly in their gliadin patterns; in most cases quantitative, but also qualitative differences were found. The amino acid compositions of single components indicated that ω-gliadins (high values for Glx, Pro, and Phe) were eluted first, followed by α-gliadins (lower contents of Pro, Phe and, in some cases, of Glx and higher contents of most other amino acids). The last components to be eluted were the γ-gliadins; differences, in comparison with α-gliadins, are mainly due to the higher values for Pro, Met, Phe, and Lys and lower values for Glx, Tyr, and His. The determination of N-terminal amino acid sequences confirmed the existence of only three protein types in the gliadin fraction: ω-, α-, and γ-gliadins. Within these groups, the components are very similar; the small differences are obviously caused by exchange, insertion and/or deletion of single amino acids in the protein chain.