How do you find the actual location of a gene

[dlouis]

Hi everyone. I just found out about this site and hopefully someone knows the answer to my question.

HOW DO YOU FIND THE LOCATION OF A GENE/OPERON? For my molecular genetics class, I have to find the location of the lux genes in V. fischeri. I've read a lot online that you can amplify DNA using PCR to get the sequence but that doesn't make sense to me. How can you take the results of PCR to find the location? Isn't the only thing PCR tells is the size of whatever you're looking at?

Secondly, would complementation work? I feel like if I add a plasmid with a mutated luxA gene, I would knock out the function of luxA thereby telling me where it is? But that is more from a phenotypic viewpoint. I'm still really lost as to know you find the real sequence of nucleotides.

Thanks a bunch in advance!

David

[mith]

you don't understand pcr at all. read up on it.

[MrMistery]

Actually PCR will not tell you where the gene actually is. It will tell you if you have your gene in the particular DNA molecule you put in your PCR mix. If you want to know where the gene is, I guess sequencing would be easiest.