wacky RNA gel - (Feb/14/2010 )
I ran a gel some RNA that I isolated from brain tissue using Trizol. In 4 of the samples there is a bright, high molecular weight band. The four samples with the band also had very high RNA concentrations according to the nanodrop.
I attached a picture of the gel. The first two lanes are ladders and the rest are my samples. The gel is 2% agarose. The samples were in RNA loading buffer (with a denaturing reagent).
Could it be genomic DNA? What else could cause the bright band? Also, how could genomic DNA get into my sample? I used Phase lock gel tubes during the isolation, which are supposed to confine the DNA below the gel.
I think there is still impurities in your sample for which it is stuck in the wells and is giving a smear if there is degradation of the same. I have seen it in my samples but if you want to use that RNA reprecipitate it using common methods. I hope this helps.