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: The ATM protein is a single , high - molecular weight protein predominantly confined to the nucleus of human fibroblasts , but is present in both nuclear and microsomal fractions from human lymphoblast cells and peripheral blood lymphocytes .
### Output Text:
The ATM protein is a single , high - molecular weight protein predominantly confined to the nucleus of human fibroblasts , but is present in both nuclear and microsomal fractions from human lymphoblast cells and peripheral blood lymphocytes . 