Thank you Malcom and David,
In doing some digging I did find another thread about Anti-M a few years ago that both of you gave input on, and it was a similar situation but perhaps more tube testing rather than gel.
Sorry about calling cells homozygous, Malcolm - what is the correct name for an M+, N- cell and an M+, N+ cell? Just MM and MN - no homos or heteros?
Maryann