DNA molecules (I), corresponding to the sequence of the major allergens of cereal pollen are new. (I) have sequences (1； 1603 nucleotides (nt))； (3； 1644 nt)； (5； 1608 nt)； (7； 1603 nt) or (9； 1603 nt), all reproduced. DNA molecules (I), corresponding to the sequence of the major allergens of cereal pollen comprise sequences comprising 1603 nucleotides (SEQ ID No.:1) (nt))； 1644 nucleotides (SEQ ID No.:3； )； 1608 nucleotides (SEQ ID No.:5； )； 1603 nucleotides (SEQ ID No.:7； ) or 1603 nucleotides (SEQ ID No.:9； ). Independent claims are also included for: (1) DNA (Ia) that hybridizes to (I) under stringent conditions and is derived from DNA of Poaceae； (2) DNA (Ib) that encodes a polypeptide that is immunologically cross-reactive with the major allergens Sec c 4 ( Secale cereale)； Hor v 4 ( Hordeum vulgare) or Tri a 4 ( Triticum aestivum) and derived from Poaceae； (3) DNA fragment, or combination of fragments, of (I), (Ia) or (Ib) that encodes an immunomodulatory T-cell reactive fragment (X) of Group 4 Poaceae allergens； (4) a DNA corresponding to any of the new DNAs or fragments that encodes an (X) but is modified by targeted mutation of individual codons, deletion or addition； (5) recombinant DNA expression vector or cloning system containing any of the new DNAs linked to expression control sequences； (6) host organism transformed with any of the new DNAs or the vector of (5)； (7) preparing a polypeptide (II) encoded by the new DNAs by culturing the organisms of (6)； and (8) (II) having any of the sequences, comprising 518 amino acids (SEQ ID No.:2； 520 amino acids (SEQ ID No.:4； )； 518 amino acids (SEQ ID No.:6； )； 518 amino acids (SEQ ID No.:8) or 518 amino acids (SEQ ID No.: 10； ) or their mature forms. ACTIVITY : Antiallergic. No biological data given. MECHANISM OF ACTION : Vaccine.
