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: Insulin gene region contributes to genetic susceptibility to , but may not to low incidence of , insulin - dependent diabetes mellitus in Japanese .
### Output Text:
Insulin gene region contributes to genetic susceptibility to , but may not to low incidence of , <span class="disease">insulin - dependent diabetes mellitus</span> in Japanese . 