Sequence comparison of the right end of fowl adenovirus genomes.

The nucleotide sequence at the right end of the genomes of fowl adenoviruses (FAdVs) representing species groups C (FAdV-4 CA and FAdV-10 C-2B), D (FAdV-2 CA), and E (FAdV-8 CA) was determined and analyzed and compared to FAdV-1 (species group A virus) and FAdV-9 A-2A (species group B virus). High nucleotide sequence identities and amino acid identities (74-94%) were found among viruses in the same species group. Homologues to known open reading frames (ORFs) of the right end of the reported FAdV genomes, such as lipase and Gam-1, were also found in all analyzed viral genomes. Homologues to a few FAdV ORFs were found in viruses other than FAdVs as well. Several novel FAdV ORFs were also found. Most identified ORFs have unknown function and thus further studies are necessary to establish their importance in virus replication. ORF content within the right end of the FAdV genomes varied among FAdVs, while the gene order and orientation of shared ORFs are conserved between different FAdVs.