New findings suggest that an estimated 40% of open reading frames in fully sequenced organism have unknown biochemical functions and no relationship to known genes. Therefore global , genome-wide approaches to determine gene function are launched. What kinds of functional assays are there to study these genes ? something like RAGE ( Random Activation of Gene Expression) methodology.

Can you tell me some more about the methodology for that?

In bacteria it would be development of transposon knockouts for these genes. Then various assays to see what the disruptions did.