amount of DNA for low copy number gene - (Sep/03/2006 )

if i am looking for a low copy number gene in southern blot then what should be the amount of DNA i should load inwell to get a signal of x ray film.

that would depend on how big the genome of the organism you are using. Thus the percentage of your gene to total DNA. How long are you willing to expose the x ray film for. How well your probe binds. How much probe do you use.

If you give more info, somebody could some along and supply a better answer.

But since I have the provobial microphone, I shall blindly stab at 10 microgram of eukaryote genomic DNA with X-ray exposure time of 5 days at -80C.