In the sentence extracted from biomedical literature, identify all the disease entities. The required answer format is the same sentence with HTML <span> tags to mark up specific entities. 
### Entity Markup Guides:
Use <span class="disease"> to denote a disease.

### Input Text: Our study indicates that chain - terminating mutations located in the 3 part of APC do not result in detectable truncated polypeptides and we hypothesize that this is likely to be the basis for the observed AAPC phenotype . .
### Output Text:
Our study indicates that chain - terminating mutations located in the 3 part of <span class="disease">APC</span> do not result in detectable truncated polypeptides and we hypothesize that this is likely to be the basis for the observed <span class="disease">AAPC</span> phenotype . . 