This protocol was developed by Arun Subramaniam from Proctor and Gamble.

1. Digestion of the tail clip:
• Cut about 50-100 mgs of tail into an eppendorf tube containing 500ul of tail prep solution:
• 50mM Tris pH 8.0
• 100mM EDTA
• 100mM NaCl
• 1% SDS
• 750ug Protease K/ml
• Incubate at 60°C overnight (or until digestion is complete)
• Add 0.5ml phenol, mix well, spin for 10' @ 10,000 rpm at room temperature
• Remove aqueous phase.  To the aqueous phase, add 0.5ml phenol/chloroform, mix well, then spin for 5' @ 10,000 rpm at room temperature
• Remove aqueous phase.  To that phase, add 0.5ml cold 95% EtOH and mix well.  You will see a white ball of ppt form; that is the genomic DNA
• Spool out DNA with pipette tip.  (You actually dig the DNA out with the tip, rather than spooling it)
• rinse DNA in 70% EtOH (cold), and then in 95% EtOH (cold).  Air dry and dissolve in 200ul TE
• Use 2ul of DNA solution for estimation of concentration
  
  
2. Restriction digests of genomic DNA:
• Use 10ug of DNA in a total volume of 300ul
• Allow water, buffer, and DNA to sit together 10-15 minutes at 37°C prior to adding enzyme
• Digest the DNA > 7 hours
• Precipitate the DNA with 2 volumes of EtOH (best to do overnight)
• Spin, then wash with 70% EtOH
• Dry, then resuspend in 18ul of water
• Heat the DNA at 65°C for about 10' prior to loading on the gel
• Add 2ul of gel loading dye
• Run the gel slowly (about 4V/cm)