6853
In an effort to contribute to the transcript map of human chromosome 21 and the understanding of the pathophysiology of trisomy 21 , we have used exon trapping to identify fragments of chromosome 21 genes .
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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:  
Answer:
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