17966
Smokers with valine ( Val ) / Val genotype , compared with methionine ( Met ) carriers , had greater negative subjective effects from IV nicotine and had more severe withdrawal severity following overnight abstinence from smoking .
 Chemical: valine; Chemical: Val; Chemical: Val; Chemical: methionine; Chemical: Met; Chemical: nicotine
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: valine; Chemical: Val; Chemical: Val; Chemical: methionine; Chemical: Met; Chemical: nicotine