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RESULTS Six of 8 monozygotic ( MZ ) twin pairs were disease concordant , compared with 4 of 15 B27 - positive dizygotic ( DZ ) twin pairs ( 27 % ) and 4 of 32 DZ twin pairs overall ( 12 . 5 % ) .
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Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Disease 
Text: {0} 
Answer:
 None