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: FISH studies in a patient with sporadic aniridia and t ( 7 ; 11 ) ( q31 . 2 ; p13 ) .
### Output Text:
FISH studies in a patient with <span class="disease">sporadic aniridia</span> and t ( 7 ; 11 ) ( q31 . 2 ; p13 ) . 