2. The study of genomes recovered from environmental samples as opposed to getting them from clonal cultures.
The technique is to clone DNA in large fragments directly from the microorganism's environment; (soil or oceans) into a culturable host and conduct a sequence-based and functional genomic analysis on it.
The hope of this new strategy is isolate new chemical signals, new secondary metabolites that might have utility to humans, and the reconstruction of an entire genome of an uncultured organism.
This relatively new field of genetic research allows the genomic study of organisms that are not easily cultured in a laboratory.
In 1998, Jo Handelsman, a plant pathologist at the University of Wisconsin-Madison and four colleagues coined the term metagenomics, literally, "beyond genomics".
Metagenomics has also been described as "the comprehensive study of nucleotide sequence, structure, regulation, and function".
Scientists can study the smallest component of an environmental system by extracting DNA from organisms in the system and inserting it into a model organism. The model organism then expresses this DNA where it can be studied using standard laboratory techniques.