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将两株１型犬腺病毒（Ｃａｎｉｎｅａｄｅｎｏｖｉｒｕｓｔｙｐｅ１，ＣＡｄ１）ＤＮＡ片段（２９～４０ｍ．ｕ．）和两株２型犬腺病毒（ＣＡｄ２）ＤＮＡ片段（２８～４４ｍ．ｕ．），分别克隆到质粒ｐＢｌｕｅｓｃｒｉｐｔＳＫ中。经核苷酸序列测定和计算机分析表明，在上述克隆片段内，两株ＣＡｄ１（ＣＬＬ和Ｇｌａｘｏ）的序列相同，两株ＣＡｄ２（Ｔｏｒｏｎｔｏ和Ｃｈｉｎａ）的序列也相同；ＣＡｄ１与ＣＡｄ２具有９１．３％的序列一致性，而ＣＡｄ１与人腺病毒２型（ＨＡｄ２）有６０．５％的序列一致性。最重要的是发现１、２型犬腺病毒基因组均缺失ＶＡＲＮＡ编码区序列，因此表明ＶＡＲＮＡ与犬腺病毒两型之间的毒力差别，以及同型强弱毒株之间的毒力差异没有关联，ＶＡＲＮＡ在犬腺病毒持续感染中也不起作用。另外发现，犬腺病毒末端蛋白前体的主体外显子及其剪接受体位点是保守的。还推断了犬腺病毒５２．５５ｋＤ蛋白的启始密码子的可能位点。
Two DNA fragments (29 ~ 40m.u.) Of Caninea adenovirus type 1 (CAd1) and two DNA fragments of canine adenovirus type 2 (28 ~ 44m.u.) Were cloned into plasmid pBluescriptSK in. Nucleotide sequence analysis and computer analysis showed that the sequences of the two CAd1 (CLL and Glaxo) were the same in the above cloned fragment, and the sequences of the two CAd2 (Toronto and China) were the same; CAd1 and CAd2 had 91.3% , While CAd1 has 60.5% sequence identity with human adenovirus type 2 (HAd2). Most importantly, it was found that the VARNA coding region was deleted in both canine adenovirus type 1 and 2 genomes, thus indicating no association between the virulence differences between VARNA and canine adenoviruses and differences in virulence between homotypes , VARNA also does not work in the case of persistent infection with canine adenovirus. In addition, the canonical exon and its splice acceptor sites of the canine adenovirus precursor protein were found to be conserved. A possible site for the start codon of the 52.55 kD protein of canine adenovirus was also deduced.