The Marek’s disease virus (MDV) induces T-cell tumors in susceptible chickens. Of the 80 to 100 known MDV genes, only the MDV MEQ gene was shown to have transforming properties. Further evidence that MEQ is probably the principal oncogene in MDV came when researchers used overlapping cosmid clones of MDV and demonstrated that deleting MEQ…

Marek’s disease (MD) is a lymphoproliferative disorder of domestic chickens caused by a highly contagious and oncogenic α-herpesvirus, Marek’s disease virus (MDV). MD is characterized by bursal–thymic atrophy and rapid onset of T-cell lymphomas that infiltrate lymphoid tissues, visceral organs, and peripheral nerves with severe clinical signs that…