Myke, There are some genomic primers that one might expect to be nearly universal, at least in regard to fishes (or "almost" fishes :-)) because they bracket genomic regions coding for such critical and highly conserved cellular machinery as ribosomes. Despite that they are themselves conservative, they may bracket regions that are not. As an example, the internal transcribed spacer (ITS) region of the ribosomal gene is not translated into protein, it merely sits between (spaces) two regions coding for ribosomal subunits (See Hillis et al. 1996). Primers that contain translated subunit sequences should work for a wide variety of organisms, while the amplified spacer region may be highly variable depending on the species and it's natural history. Primers for the ITS regions are commercially available, and I don't think that this is the only example from genomic DNA.
As for the tenmer primers: In a RAPD (or AP-PCR) study you want the primer annealing to be somewhat sloppy so that you can examine more regions. If you are considering such a marker, don't worry unduly that you don't know where the primed region is; if it is the same in other specimens, it should yield similar bands. For reason of achieving this "sloppiness", the primer will be shorter than that which you might use when targeting a specific genomic. Of course, even a short primer for targeted region will have high fidelity under high annealing temperatures, so it could be appropriate where a known conserved region suitable for priming is short.
I hope this helped. Feel free to contact me off-list for clarification.
Myke Bon wrote:
> Greetings Fish People, > I'm doing research on Lamprey in Alaska and at the point now that I > need to perform PCR on the DNA I do have for L. tridentada. The > problem I have is that I need to determine a primer to use for the > process. I've been to the Gene Bank though all information there is > mitochondrial; I'm working with genomic DNA. > > We've been told it would be ideal to use a 10mer primer for > polymorphism research though most literature I've found suggests > between 18-29 for PCR. So my question is as follows: > > 1)Can someone suggest how I can determine a primer for a species that I > dont know the Genomic Map on? We have access to mitochondrial map of > L. fluviatis, It has been recommended we use it for a guideline to work > with L. tridentada, though we can't use it for genomic work I think. > Is there a universal primer (such as 'alu')that can work? Any > suggestions will be recieved with great enthusiasm. > > Thanks in advance! > > Myke Bon > > ><> ><> ><> ><> ><> ><> ><> ><> ><> ><> ><> ><> ><> ><> ><> ><> > To leave the Fish-Sci list, Send blank message to: > mailto:[log in to unmask] > Vacation? send SET FISH-SCI NOMAIL to [log in to unmask] > ><> ><> ><> ><> ><> ><> ><> ><> ><> ><> ><> ><> ><> ><> ><> ><>
-- Thomas M. Grothues Rutgers University Marine Field Station C/O 132 Great Bay Blvd. Tuckerton, NJ 08087 (609) 296-5260 x262 [log in to unmask]
><> ><> ><> ><> ><> ><> ><> ><> ><> ><> ><> ><> ><> ><> ><> ><> To leave the Fish-Sci list, Send blank message to: mailto:[log in to unmask] Vacation? send SET FISH-SCI NOMAIL to [log in to unmask] ><> ><> ><> ><> ><> ><> ><> ><> ><> ><> ><> ><> ><> ><> ><> ><>
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