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 murine homologue of the ND gene was cloned and shown to encode a polypeptide that shares 94 % of the amino acid sequence with its human counterpart .
### Output Text:
The murine homologue of the <span class="disease">ND</span> gene was cloned and shown to encode a polypeptide that shares 94 % of the amino acid sequence with its human counterpart . 