8796
Our unexpected observations of paternal or biallelic expression of WT1 in fibroblasts and lymphocytes , together with the previous findings of maternal or biallelic expression in placentae and brains , suggest that the allele-specific regulatory system of WT1 is unique and may be controlled by a putative tissue- and individual-specific modifier .
 fibroblasts, WT1, lymphocytes, WT1
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:
 fibroblasts, WT1, lymphocytes, WT1