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: If this finding can be confirmed , it may provide an insight into the structural features of the BRCA1 protein that are important for its function .
### Output Text:
If this finding can be confirmed , it may provide an insight into the structural features of the BRCA1 protein that are important for its function . 