Qiagen or CsCl preps are best I agree, but most of us sucessfully inject
DNA preps which are treated with RNase for 1 hour, extracted 1x with
phenol/chloroform, twice with chloroform and then ethanol precipitated. The
yield of F1 progeny and subsequent lines is usually indistinguishable
from Qiagen prep DNA, and all of our cosmid injections are processed this way.
Anne Hart
Kaplan Lab
Mass. General Hospital
