The Genome of a Very Virulent Marek's Disease Virus

J Virol. 2000 Sep;74(17):7980-8. doi: 10.1128/jvi.74.17.7980-7988.2000.


Here we present the first complete genomic sequence, with analysis, of a very virulent strain of Marek's disease virus serotype 1 (MDV1), Md5. The genome is 177,874 bp and is predicted to encode 103 proteins. MDV1 is colinear with the prototypic alphaherpesvirus herpes simplex virus type 1 (HSV-1) within the unique long (UL) region, and it is most similar at the amino acid level to MDV2, herpesvirus of turkeys (HVT), and nonavian herpesviruses equine herpesviruses 1 and 4. MDV1 encodes 55 HSV-1 UL homologues together with 6 additional UL proteins that are absent in nonavian herpesviruses. The unique short (US) region is colinear with and has greater than 99% nucleotide identity to that of MDV1 strain GA; however, an extra nucleotide sequence at the Md5 US/short terminal repeat boundary results in a shorter US region and the presence of a second gene (encoding MDV097) similar to the SORF2 gene. MD5, like HVT, encodes an ICP4 homologue that contains a 900-amino-acid amino-terminal extension not found in other herpesviruses. Putative virulence and host range gene products include the oncoprotein MEQ, oncogenicity-associated phosphoproteins pp38 and pp24, a lipase homologue, a CxC chemokine, and unique proteins of unknown function MDV087 and MDV097 (SORF2 homologues) and MDV093 (SORF4). Consistent with its virulent phenotype, Md5 contains only two copies of the 132-bp repeat which has previously been associated with viral attenuation and loss of oncogenicity.

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Cell Line
  • Chickens
  • DNA, Viral / analysis
  • Genome, Viral*
  • Herpesvirus 2, Gallid / genetics*
  • Herpesvirus 2, Gallid / isolation & purification
  • Herpesvirus 2, Gallid / pathogenicity
  • Marek Disease / virology*
  • Molecular Sequence Data
  • Sequence Alignment
  • Sequence Analysis, DNA
  • Virulence / genetics


  • DNA, Viral

Associated data

  • GENBANK/AF243438