A recent paid advertisement for Bio-Rad Laboratories' TransFectin lipid reagent mentioned the benefits of using the product in conjunction with DNA-directed RNAi experiments. Although the announcement is not unusual in and of itself, the term ddRNAi has been used solely by Benitec to describe its RNAi technology.
DdRNAi describes an RNAi approach, employed by a number of companies and research institutions, that uses DNA plasmids that express dsRNA inside a cell. Though not trademarked, the ddRNAi moniker was coined by Benitec to describe its in-house technology. Another company using a similar RNAi approach, Nucleonics, has termed its technology expressed interfering RNA, for example.
The Bio-Rad advertisement appeared in an RNAi News news bulletin e-mailed to subscribers last week. Similar "product alerts" appear as paid ads in RNAi News and its sister publications, and as such are not independent editorial comments.
According to the Bio-Rad announcement, "TransFectin lipid reagent is an effective delivery mediator for DNA-directed RNAi … strategies. The … efficiency of TransFectin leads to more robust silencing of your target gene when using siRNA-expression plasmids or linear-expression cassettes."
Annette Tumolo, division manager for Bio-Rad's gene expression division, told RNAi News that the company's use of the ddRNAi term does not imply a formal licensing relationship with Benitec or Promega, which are currently involved in a legal dispute over the rights to license the technology in areas outside of human therapeutics.
She stressed that the ddRNAi reference "wasn't portentous of anything in particular. We're trying to get the customer to buy the right reagent for the right" application.