MgCl vs MgSO4 for PCR - (Apr/04/2006 )

I often wondered, why some companies supply their PCR Ingredients with MgCl and some with MgSO4. Is there ANY difference between them ?

Not much difference, won't affect normal PCR, where the key is the amount of available Mg2+. I think that SO42- might be useeful in methylation PCR, but I am not sure.

Recipes using Tris-HCl tend to use MgCl2, while recipes employing Tris-SO4/(NH4)2SO4 tend to use MgSO4.