Characterization of insertion sites and development of locus-specific assays for three broiler-derived subgroup E avian leukosis virus proviruses

This report deals with the identification of novel elements belonging to a family of endogenous retroviruses, designated endogenous avian leukosis virus-type proviral elements (ALVE), that reside in the genome of the chicken and are closely related to exogenous avian leukosis viruses. The study of ALVE elements in the chicken genome serves as a model system for understanding the interplay between endogenous viruses and their vertebrate hosts in general, including humans. In this report, we characterize the insertion sites and describe locus-specific, diagnostic polymerase chain reaction-based assays for three previously discovered, but as yet not localized, ALVE elements. In addition, we assess the proviral integrity, provide the complete element sequence and examine the genomic environs of the three broiler-derived elements.