Addgene, the non-profit plasmid repository, turned 5-years-old this year. That’s five years longer than some of the scientists Addgene first approached to deposit plasmids thought we would last (I can say “we” because I’m a Senior Scientist at Addgene).

Not only have we lasted, but we’ve thrived. Addgene recently stored its 10,000th plasmid, and our hard-working technicians are sending out nearly 200 plasmids a day to labs all over the world.

Not too shabby, but to maintain its position as the place to go for plasmid archiving and distribution, Addgene has added some new features. One is very simple and is aimed scientists searching and requesting plasmids: the flame.

After having to answer countless e-mails from researchers who were concerned about ordering a plasmid that was not field-tested extensively, we decided to just let people know which plasmids were the most popular.

A plasmid with a yellow flame has been ordered at least 20 times. After 50 requests, the flame turns red; after 100 requests, the flame turns blue. In case you’re curious, our most popular plasmid is Didier Trono’s pMD2.G (a lentiviral packaging vector), which has been requested over 1,200 times. That’s what I call field tested. Click here to check it out.