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: We describe herein , to our knowledge , for the first time , the cloning of a full - length cDNA for ATM and correction of multiple aspects of the radio - sensitive phenotype of A - T cells by transfection with this cDNA .
### Output Text:
We describe herein , to our knowledge , for the first time , the cloning of a full - length cDNA for ATM and correction of multiple aspects of the radio - sensitive phenotype of <span class="disease">A - T</span> cells by transfection with this cDNA . 