Representational difference analysis

Successful pathogens have evolved a variety of specific gene products that facilitate their survival and growth within the host, as well as mechanisms to regulate expression of these virulence-associated genes in response to their environment. In comparison with commensals, the pathogenic phenotype can thus be seen as a consequence of both differences in gene content and gene expression. Not surprisingly, identification of these differences is a frequent goal in modern biomedical research, and as a result, a variety of differential screening methods have been developed over the last few years (1,2).