We report the sequence analysis of a Drosophila melanogaster (Dm) P1 genomic clone (DS05563) which contains the gamma-chaperonin-encoding gene, Cctg. The (Hs) Cctg orthologue was found to share strong sequence identity with a 1603-bp region of DS05563, suggesting that Dm Cctg is located within this region. Detailed analysis has shown that Dm Cctg comprises four exons and is interrupted by three introns of 55, 85 and 66 bp. Dm Cctg encodes a predicted peptide of 545 amino acids (aa) (approx. 60 kDa). The predicted Dm CCT gamma aa sequence shares a high degree of sequence identity with gamma-orthologues from human (70%), mouse (70%), protozoa (60%) and yeast (60%), and also contains domains found in other chaperonins including bacterial GroEL, mitochondrial Hsp60 and plant Rubisco large subunit-binding protein. These data support the conclusion that the DS05563 clone contains the Dm Cctg gene.