Sponges are the most basal metazoans and consist of about 8,000 described species, with an estimated species number of more than 15,000. They are highly diverse, ecologically important and of significant commercial importance to the pharmaceutical and biomaterials industry. Thirty percent of all potential new natural medicine has been found in sponges. About 75% of the recently registered and patented active ingredients to fight cancer have been isolated from sponges. Furthermore, it appears that medicine derived from sponges can also be used for example for asthma or psoriasis treatment.
Harvesting of sponges is not an option for the production of biomedical substances. Neither are synthetic production or lab cultivation of bio-active components viable options. According to a couple of researches, isolating sponge cells and growing them in a bio-reactor under optimal conditions has the best chance of being successful. However, sponges are notoriously difficult to identify and any cell line needs to start with a properly identified donor organism.
The Sponge Barcoding Project started a couple of years ago with the aim to cover all sponge taxa, and ranging in habitat from the marine intertidal to the deep-sea, as well as freshwater. The Sponge Barcoding Project was a major partner of the Marine Barcode of Life project (MarBOL). The goal was to obtain DNA Barcodes from 8,000 taxa to provide a basis from which more extensive sampling would be directed and routine identifications enabled. Recently described type specimens curated in associated museums were targeted first and will be supplemented with unequivocally identifiable taxa.
Sponge Barcoding isn't as easy and as straightforward as one would hope. They host a large number of non-target macro- and microorganisms found in association with them. The DNA of these organisms can be co-extracted, and either co-amplified or preferentially amplified during PCR causing sequences to be difficult to read or belonging to non-target organisms. Moreover, for defense purposes, sponges produce potent bioactive compounds that can inhibit enzymatic reactions such as PCR. Another issue stems from the fact that some sponges show only very little or no variation in the standard COI region which led to developments of protocols that allow us to obtain longer sequences that contain sufficient variation. Often DNA barcodes are supplemented with ITS to enable unambiguous identifications.
That might sound as if it is too difficult to justify further efforts but on the contrary: Despite all obstacles researchers have been able to obtain DNA Barcodes for a lot of sponges and the prospects for medical research are so high that the Sponge Barcode Project should rather be on top of the priority list when it comes to the assembly of DNA Barcodes of marine animals.