Preparation of Herring Sperm DNA for Southern Blotting
1. order powder herring sperm DNA from Boehringer Mannheim (#223646
for 1 gram)
2. dissolve 0.250 g in 25 ml of ddH2O (use 50 ml conical
tube) overnight at room temperature
3. sonicate for 15 minutes on setting #4 (or several seconds on
setting #7-9)
4. shear through 18-gauge needle 10 times or more (until solution
moves easily through needle)
5. store in labeled box (common) at –20ºC in 1 ml aliquots