4883
In comparison , a splice - blocking AHR2 morpholino used to down - regulate ahr2 expression significantly reduced the inhibition of vtg1 , vtg2 and vtg3 by 400 pptr 2 , 3 , 7 , 8 - TCDD ( 20 . 7 - 27 . 4 % rescue ) .
 Chemical: 2 , 3 , 7 , 8 - TCDD
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
Answer:
 Chemical: 2 , 3 , 7 , 8 - TCDD