APC and ovarian dysfunction: This is difficult to address in the case of Cdh1f/fGdf9-iCre females because of their ovarian failure and impossible to measure in the case of Apc2f/fZp3Cre females because a lack of APC/CCdc20 activity causes arrest in metaphase I. However, microinjection of Apc2 mRNA into Apc2f/fZp3Cre oocytes should restore APC/CCdc20 and thereby anaphase.