DEVELOPMENT OF A SET OF OLIGONUCLEOTIDE PRIMERS SPECIFIC FOR GENES ATTHE GLU-1 COMPLEX LOCI OF WHEAT

Specific amplification of the complete coding region of all six high-m olecular-weight (HMW) glutenin genes present in hexaploid wheat was ob tained by the polymerase chain reaction (PCR). Primers specific for th e N-terminal region of the 1Dx gene and for the repetitive domain of t he y-type HMW glutenin genes were also developed. Although the primers were constructed on the basis of the nucleotide sequences of HMW glut enin genes present in T. aestivum L. cv 'Cheyenne', they were very eff icient in amplifying HMW glutenin genes of diploid and tetraploid whea t species. PCR analysis of HMW glutenin genes of T. urartu Tuman., T. longissimum (Schweinf. & Muschl.) Bowden and T. speltoides (Tausch) Gr en. ex Richt. showed a high degree of length polymorphism, whereas a l ow degree of length variation was found in accessions of T. tauschii ( Coss.) Schmal. Furthermore, using primers specific for the repetitive regions of HMW genes, we could demonstrate that the size variation obs erved was due to a different length of the central repetitive domain. The usefulness of the PCR-based approach to analyze the genetic polymo rphism of HMW glutenin genes, to isolate new allelic variants, to esti mate their molecular size and to verify the number of cysteine residue s is discussed.