Consists of a fragment encoding a deleted form of ref(2)P (amino acids 92-599, numbering relative to the sequence of ref(2)P+++.O1.cCMa, are deleted). The PB1 domain contains the d, p and p' polymorphisms derived from ref(2)Pn. The d polymorphism consists of amino acid residues Q28 and N29 (in the PB1 domain) being replaced by a single G residue. The p polymorphism consists of amino acid residue I32 being replaced by a V residue. The p' polymorphism consists of amino acid residue Q43 being replaced by a L residue.
ref(2)Pdpp'.Δ92-599.cCMa is restrictive for sigma virus multiplication.
ref(2)Pdpp'.Δ92-599.cCMa fails to rescue ref(2)Pod3/Df(2L)E55
ref(2)Pod3/Df(2L)E55 males carrying ref(2)Pdpp'.Δ92-599.cCMa are sterile.