2115
Whereas IDUA , IDS , NAGLU and ARSB demonstrate similar levels of mutation heterogeneity ( 0 . 6 - 0 . 675 different mutations per total alleles ) , SGSH and GALNS have lower levels of mutation heterogeneity ( 0 . 282 and 0 . 455 , respectively ) , due to more recurrent mutations .
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Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
Answer:
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