8159
This is the first study in which mutation screening has been performed for both the EXT1 and EXT2 genes prior to any linkage analysis .
 GENE: EXT1; GENE: EXT2 genes
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: EXT1, EXT2 genes 
Answer:
 GENE: EXT1; GENE: EXT2 genes