7230
It is suggested that the observed clinical phenomena in response to morphine can be explained by differences in expression and sensitivity of some opioid receptor subtypes in migraine .
 GENE: opioid receptor
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: GENE 
Text: {0} 
 Entities: opioid receptor 
Answer:
 GENE: opioid receptor