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: Mutation analysis in 19 families of German , Swiss and Turkish descent by single - strand conformation polymorphism and sequencing resulted in the detection of seven novel and 10 known mutations .
### Output Text:
Mutation analysis in 19 families of German , Swiss and Turkish descent by single - strand conformation polymorphism and sequencing resulted in the detection of seven novel and 10 known mutations . 