A series of examples of the application of recombinant nucelic acid te
chnology to the production of transgenic organisms is presented. The r
eview considers the distinct advantages of producing certain recombina
nt biomolecules in appropriate eucaryotic systems rather than in the t
raditional procaryotic ones. Gene therapy in humans and the production
of transgenic animals and plants are discussed. Concerns about the in
advertant construction of new pathogens and ethical considerations abo
ut interfereing with poorly understood ecosystems are addressed.