A novel protein-coding ORF72.2 gene was identified from Marek's disease virus strain CVI988.

Marek's disease is a highly contagious disease of poultry characterized by rapid-on set of T-cell lymphomas, which is caused by Marek's disease virus (MDV), but its pathogenic mechanism is still not very clear. Recently, some new progress were achieved in molecular character of MDV. Along with the genomic sequencing of MDV serotype 1, some novel open reading frames (ORFs) were predicted, and ORF72.2 was one of them which have no homologues in other MDV serotypes or in other alphaherpesvirus. In the study, ORF72.2 was firstly identified as a protein-coding gene by the method of reverse transcription polymerase chain reaction (RT-PCR), western blotting and indirect immunofluorescence assay. This study paved the way to conduct further studies to determine whether ORF72.2 plays a role in MDV replication and pathogenicity.