Hi folks, Many thanks to those of you who responded to my query about extracting DNA from molted insect cuticles. Below is a summary of the answers I received. A colleague also referred me to this publication: http://ddr.nal.usda.gov/bitstream/10113/39588/1/IND43638893.pdf Thanks again, Rob Dr Rob Cruickshank Lecturer in Entomology Department of Ecology Burns Building, Room B522 PO Box 84 Lincoln University Lincoln 7647 Christchurch, New Zealand p +64 3 321 8355 | f +64 3 325 3844 e Rob.Cruickshank@lincoln.ac.nz | w www.lincoln.ac.nz Lincoln University, Te Whare Wanaka o Aoraki New Zealand's Specialist Land Based University Original query: I would be interested to know whether anyone has tried extracting DNA from molted insect cuticles. Responses: I have done it a few times, with variable success. The main issue is to keep PCR analyses restricted to short fragments, at least at first until you prove it works! I tend to put the whole cuticle in a suitable volume of the following buffer (enough to cover) 10mM Tris 10mM NaCl 5mM CaCl 2.5mM EDTA 10% final volume Prot K solution (may be overkill to use this much) 40mM DTT 2% final volume SDS Then incubate for some hours/overnight at 55C. The cuticle won't dissolve, but should yield some DNA. I then purify the liquid using something like a Qiaquick PCR clean up kit (you just pretend the buffer is a PCR....) and elute into a small amount of EB (say 50ul). > Many years ago we did some tests on molted butterfly cuticles (I don't even remember the species) using a Guanidium/silica particles method byGerloff et. al. (I guess this is the primary reference). Results were very good, but we tested just a few samples. I would definitely do some more test if I was on such a project. > We have had OK DNA from larval butterfly head capsules, and from Onychophoran shed skins. > Try searching google scholar for "exuviae DNA". Extraction protocols have been developed for many different arthropods/insects. > My lab has tremendous success in getting mitochonrial sequences from empty fly puparia from various families. Getting nuclear genes appears to be more difficult, as you might expect, and we haven't yet done much. We are in the final stages of manuscript preparation on the mitochondrial data. > I have successfully extracted DNA from the pupal exuviae of bees. I had hoped to use these for non-destructive genotyping at microsatellite loci. However, I find that the genotyping results are highly inconsistent - I was getting different allele calls on each separate run. I did not invest too much energy in troubleshooting before giving up. You might be able to get better consistency with more replicates, as is standard for mammalian fecal samples. Best of luck! > I was getting good yields from tarantula exuvia. Here is the paper*. It has been a while but I can try to answer any questions you might have. *The paper that was sent can be found at http://dx.doi.org/10.1007/s10592-006-9173-2 "The contents of this e-mail (including any attachments) may be confidential and/or subject to copyright. Any unauthorised use, distribution, or copying of the contents is expressly prohibited. If you have received this e-mail in error, please advise the sender by return e-mail or telephone and then delete this e-mail together with all attachments from your system." Robert.Cruickshank@lincoln.ac.nz