What are some things to consider if my yeast knockout strain does not seem to be the correct mating type after I have tested my strain by sporulation or mating?
Some things to consider for the yeast knockout strains:
1.) Did you perform a PCR verification for the strain? (http://www-sequence.stanford.edu/group/yeast_deletion_project/project_desc.html#delconfirm)
2.) For your mating protocol, what is the genotype of the tester strain?
3.) Are you using any controls for the mating protocol?