Help explain my DNA bands smearing

[ryan at mbcf.stjude.org]

In article <445jck$g5c at merlion.singnet.com.sg>, j140474 at singnet.com.sg(jene) writes:
> Hello, recently I did a gel electrophoresis on genomic DNA isolated from 
> Arabidopsis. The samples were restricted with MluI, EcoRI and SAU3A.
> I expected to see distinct bands of DNA but ended up with smears in all 
> my lanes. No bands can be made out at all. The markers came out all righ. 
> 
> What is the smearing due to? Was it caused by multiple site restriction?
> Can I solve the problem?
> 
> Anybody who can help please post back a reply to this Newsgroup. Thanks! 
> 

Hi Jene,

How did you visualize your DNA? Blot hybridization to a specific probe DNA will
light up only fragments that contain bases complementary to the probe. Staining
with e.g. ethidium bromide will show all fragments, all sizes (i.e., a smear).

Kevin 
-- 
--
       	==========================================
	Kevin W. Ryan
	Department of Virology & Molecular Biology
	St. Jude Children's Research Hospital
	Memphis, Tennessee 38101-0318, U.S.A.
	
	phone: (901) 495-3411
	fax:   (901) 523-2622
	Internet: ryan at mbcf.stjude.org
	==========================================