12193
Butyric acid ( BA ) is known to induce overexpression of fetal hemoglobin and then erythroid differentiation .
 fetal hemoglobin
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: cell line, protein, RNA, DNA, cell type 
Text: {0} 
Answer:
 fetal hemoglobin