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: However , a single mutation was observed in 32 / 33 defective ATM alleles in Jewish A - T families of North African origin , coming from various regions of Morocco and Tunisia .
### Output Text:
However , a single mutation was observed in 32 / 33 defective ATM alleles in Jewish <span class="disease">A - T</span> families of North African origin , coming from various regions of Morocco and Tunisia . 