Linda,
The first link will take you directly to the A1B1 description, the second link to the page listing all documented markers. Good information! It appears that A1B1 is found by FISH analysis, so if your tissue block is being stored you could perhaps have it tested for this marker.
Hugs,
Lolly

Lolly: You are a super friend! Thank you so much for finding out this information. I WOULD like to have my tumor sample tested by FISH for the AIB1 estrogen receptor. I have no idea if any of my tumor(s) (there were 3) were saved. I guess I will call the hospital tomorrow to see what I can find out. I'll keep my fingers crossed that there is a little piece of me stashed someplace. Thanks Again. Linda