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: Although this patient did not have a detectable deletion within PAX6 , her aniridia may have resulted from a disruption of the distal chromatin domain containing either enhancers or regulators for PAX6 .
### Output Text:
Although this patient did not have a detectable deletion within PAX6 , her <span class="disease">aniridia</span> may have resulted from a disruption of the distal chromatin domain containing either enhancers or regulators for PAX6 . 