2724
Also , the BALB / c gene contains a single substitution in a conserved octamer sequence approximately equal to 100 nucleotides upstream of the coding region , which could affect its expression .
 BALB / c gene
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: GENE 
Text: {0} 
Answer:
 BALB / c gene