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DNA extraction from oilseed plants - (Jan/30/2006 )

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I am extracting genomic DNA from castor plant. I am used to run the DNA sample on 0.8% agarose gel in 1x TAE buffer. I get a very thin band of DNA on the gel. purity of my sample corresponds to 1.9. and the concentration is around 1800 microgram/ml. the genomic DNA size of castor plant is 323 million basepairs. I am suspecting it to be sheared. am I rite. if yes, how do I prevent shearing or do I need to change the gel % or else ,suggest me a possible way.

thankyou all in advance



If your DNA is sheared, it will show as a smear on the gel, not a discrete cclump or band. Avoid shearing by using cutoff tips for the solvent extractions, and avoid vigorous vortexing.



bob1 is right.

As an alternative to vortexing, try gently inverting the tube a few times whenever you need to mix things.



It's almost impossible to avoid shearing chromosomal DNA in liquid. It seldom matters, however. What is the application? For PCR, cloning, sequencing, or southern blots, your DNA should be fine.