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: Identification of a RING protein that can interact in vivo with the BRCA1 gene product .
### Output Text:
Identification of a RING protein that can interact in vivo with the BRCA1 gene product . 