How to take DNA samples from snakes?

Originally Posted by Helenthereef

Would be nice to get confirmation from anyone who's actually done it though.....

Dr. Warren Booth has done this type of testing, two parties that post on the KS boa forum this year had questionable litters (possible parthenogensis) and sent him sheds to test. I'd contact him...
http://www.zoominfo.com/people/Booth...313531528.aspx
KS post, you can find him in this thread:
http://forums.kingsnake.com/view.php?id=1798862,1798939

Good luck

Thanks!

Hey All,


I work in a genetics lab and about 90% of my job is purifying and amplifying dna. I have gotten adequate dna samples from snakes with sheds, although RNA is degraded to much to be useful.

The only issue with using sheds is contamination. During genetic testing we have to replicate or amplify the dna. During this process we would also amplify any other dna that is present-so you have to make sure the shed is not contaminated with skin cells from cage mates, other animals, yourself(super touchy if your doing pcr for sex determination).

Just use cleaned tweezers, latex/nitrile gloves to get the skin off the animal, and store in ziplock bags. Since the shed skin is already desicated cold storage really isn't that necessary, but since everyon has a fridge cold storage can only help(can't hurt).

Thanks
ben

Thanks!

Hey,

I forgot to take into account what you are trying to do here(see if a Rhac was parthogenically reproduced). So you will need to compare to offsprings dna to the dams. There is a couple ways of doing this.

If we knew the genome of a Rhac and all the known constructs were the same you could argue it was a clone. But I believe to do a more strict match(im not that familiar with clones/cloning) you have to use mitochondrial dna-this is probably cleaner(less fragmented) if a tissue clip was used. Shed is only comprised of epithelial cells, where a tissue clip would contain all levels/types of tissue(except bone in this case).

Thanks
ben

I'm not sure that mitochondrial DNA would answer the question of parthogenesis, as it always comes from the mother anyway, so any father's DNA would not be represented.

Hey,

You are correct, but in parthogenesis there is no father. So you compare the mitochondrial dna, and if there is an exact match then it is a clone, i.e parthogenesis.

If it is not a match (outside of random point mutations) then there was a male present somewhere sometime.

thanks
ben

I bow to your more current knowledge of this, but as all mitochondrial DNA always comes from the mother, wouldn't they be identical in the offspring whether there was a father involved or not? I.e, barring point mutations, all mitochondrial DNA is effectively a "clone"of the mother's.

Hey,

Now you've got me doing double takes!Lol. I'll holler at my boss tomorrow afternoon and get this double checked. He is a prof. of medical genetics-he should set it straight.

thanks
ben

Hey,

After a talk with the boss, and another professor acrossed the hall I have determined that Mitochondrial DNA I either was playing hooky or my eyes were glazed over from all the excitement of the lecture.


So Basically there is a ton of ways to see if the offspring is a clone of the adult. Some of it is more educated guesstimates, some is pretty tricky to determine 100%, and other areas have still not proven themselves to even work 100% of the time. Some of them I had no idea what laguage he was speaking and I was daydreaming.
So the quickest easiest way, with decent results for the effort would be to look at longer strands of dna from the female (over 1000base pairs) and compare them to the offspring. If you looked in say ten place (the more you do the more conclusive it is) and the long chains were identical you could argue it was a clone.

If I aborbed it correctly this time.

As for mitochondrial dna, since it is passed from the female unmolested by the males dna, they use it to look at lineages in populations to see how long ago the groups/localities cleaved, and origins/descent of populations. Becuase on a broad scheme each locality is roughly considered at a rough level a clone in thier own group. I.E. if you breed a boxer dog to a boxer dog you aren't going to pop out a german shepard.

I guess it was about time for my one annual post were I talk out of my bum and someone catches me on it. Well, this made me put out way to much effort and my head hurts now-off to gather some adult beverages and wash some rubbermaids.


thanks
ben