FISH probes - why check with gel (Jan/16/2006 )
Hey,
one of my colleagues performed a FISH for the first time, she labeled DNA (chromosomes 7 and 8) with two probes, one with biotin and the other with digoxigenin. After the nick labeling she checked it with a 2 % agarose gel, probably because of the size, right??? But why was she doing the gel anyway??? I'm sorry, I have absolutely no clue about FISH, but she said that she wanted to ask me some questions and I don't want to look like a complete dork... 
Need to check that the transcription reaction (here including the incorporation of the labelled nucleotides) has worked efficiently i.e. was any probe made? Also to check that the size of the probe generated is appropriate (too small or too large can increas background, and you would therefore need to adjust strigency of washes etc).
one of my colleagues performed a FISH for the first time, she labeled DNA (chromosomes 7 and 8) with two probes, one with biotin and the other with digoxigenin. After the nick labeling she checked it with a 2 % agarose gel, probably because of the size, right??? But why was she doing the gel anyway??? I'm sorry, I have absolutely no clue about FISH, but she said that she wanted to ask me some questions and I don't want to look like a complete dork...