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: The third patient ( with AO2 ) had the R279W mutation compounded with a novel mutation , the deletion of cytosine 418 ( delta c418 ) , predicting a frameshift with premature termination .
### Output Text:
The third patient ( with <span class="disease">AO2</span> ) had the R279W mutation compounded with a novel mutation , the deletion of cytosine 418 ( delta c418 ) , predicting a frameshift with premature termination . 