Working at a plasmid repository, I get a lot of feedback from scientists who are relieved we exist simply because that means they don’t have to request a plasmid directly from another academic lab. Either they’ve had a bad experience making requests in the past, or they really don’t know how to go about doing it in a professional manner.

Nothing you can do will guarantee that a plasmid request will be fulfilled, but here are a few rules of etiquette to consider. Note that I’m talking about plasmids, but most of these “rules” can be applied to nearly any biological reagent:

Asking for the Plasmid

1. Introduce yourself and explain why you want the plasmid

Remember that you are essentially asking your colleague for a favor. Yes, if a scientist publishes a plasmid,   there is an obligation to distribute it, but remember who put in the work to make the reagent. Explain who you are, where you found out about the plasmid, and if possible, explain how you might be using it. An ethical scientist should provide you with the plasmid (and an annotated map of the plasmid) regardless of how  you’re using it, but if  you can demonstrate that you’re not a direct competitor, that might move things along for you.

2. Pay for shipping

This one might seem like a no-brainer, but I’ve talked to scientists who had essentially stopped honoring plasmid requests because they were spending a small fortune on shipping. Asking a scientist to send a reagent and pay for the shipping takes some hutzpah. Cough up your FedEx number and you’ll likely get your plasmid a lot faster.

3. Cooperate with the Material Transfer Agreement (MTA) process

The vast majority of plasmid sharing between academic labs is probably done outside the MTA process. That might be the easiest way of doing things for the parties involved, but it’s not necessarily the best (or legal) way.  Many institutions, especially HHMI, are quite rigid about their MTA guidelines and they require researchers to fill them out for every reagent that’s sent out. Don’t begrudge scientists for making you fill out this paperwork–they’re just following the rules. That plasmid you’re requesting is technically “owned” by the institution, not the lab.

After Receiving the Plasmid

1. Show some gratitude

Congratulations! You received your plasmid. Be polite and say thank you. You never know when you might run into this person at a meeting or want to propose a collaboration.

2. Make sure you received what you asked for

Before you go transfecting cells all willy-nilly, you better make sure this plasmid is what you think it is. At the very least, you should do a diagnostic digest. But to really be on the safe side, sequence it. Whether the lab published on this plasmid 1 month ago or 10 years ago, mistakes can be made. Play it safe and do some testing before you commit to an important experiment. If you do find that the plasmid has a problem, let the person who gave it to you know, diplomatically.

3. Acknowledge

If you publish anything that uses these requested reagents, give credit where credit is due. Not only is it the right thing to do, but but it will send people to the right lab should they read your paper and want to request the plasmid in question. Unless you modified the plasmid in some way, you should not be redistributing it without the original lab’s permission. A proper acknowledgment should prevent the issue from arising.

And finally, if you’ve ever used Addgene, you know that we take care of a lot of these steps for you. If you see a published plasmid that you want and it’s not already in the Addgene repository, e-mail and let us know. We’ll request it for you (and take care of some of the quality control, AND take are of the MTAs).

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  1. Kurt and Ted probably won’t see my reply since they commented quite some time ago, but as this post is currently “featured”, maybe they’ll catch my answers.

    Kurt – Well, honestly, I don’t have a great answer for you right now. It’s something that Addgene has to take into consideration when we accept deposits, but it hasn’t come up much so far. As I understand it, the companies that that do custom cloning or synthesis can claim some distribution rights. Anyone who has a company do their cloning should look at the fine print and make sure they can still distribute the plasmids to colleagues at academic institutions.

    Ted – The obligation to distribute a plasmid from a federally funded lab in the US is a legal one, but good luck finding the person in charge of enforcing that rule. You don’t want to get tangled up with the NIH any more than you would the Japanese government. You might consider notifying the journal in which a plasmid was published. Most reputable journals make publication contingent upon sharing the described reagents. Again, this does not appear to be enforced on a regular basis, but that’s most likely because few people complain in the first place. What if more people contacted journals and said “Dr. So-and-so published this paper in your journal but now refuses to acknowledge my request for a plasmid described in your article”?

    That’s the stick approach. You could also try a carrot: if you’re really desperate, offer to put the scientist’s name on your paper. You shouldn’t have to do this, but if it means the difference between publishing and graduating this year or next year, you could consider it. Not a lot of scientists can pass up their name on a paper.

    Ultimately, there are no realistic avenues for forcing a scientist to share reagents, plasmids or otherwise. It really comes down to an ethical obligation, and as we all know, not every scientist is ethical. At the very least, try to accumulate some good plasmid sharing karma. Garner a reputation for sharing your own reagents and hope your colleagues will live by the Golden Rule.

  2. The article mentions that the scientist is obliged to distribute the plasmid, but I’m wondering how strong this obligation is?

    Using all the guidelines in this article, I’ve had mixed success getting plasmids. In good cases, these correspondences have opened the door to friendly ongoing relationships. But in the bad case, I’ve heard nothing back from the author.

    For a plasmid I really need, I’ve made several requests (all very friendly) to the corresponding author, and then, partially in desperation, to the first author. No replies from anyone, dead silence. I checked the journal that published their work and they don’t specify a redistribution policy. The authors are funded by Japanese government research grants which might specify a redistribution policy, but I really don’t want get tangled up in all that.

    Is there a good way to put a tiny bit of friendly pressure on the corresponding author?

    Thanks for any tips!!

  3. This outlined procedure is the one that has been used for the last 30 years. But hove will that change now when it’s getting more and more common that plasmid constructs are designed in the computer, and then synthesized by a company? Does anyone have practical experience of getting a construct synthesized in vitro?

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