4805
The mouse beta 2 - syntrophin gene ( > 33 kilobases ) contains seven exons , all of which have homologues at the corresponding position in the alpha 1 - syntrophin gene .
 mouse beta 2 - syntrophin gene, alpha 1 - syntrophin gene
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: GENE 
Text: {0} 
Answer:
 mouse beta 2 - syntrophin gene, alpha 1 - syntrophin gene