1137
Whether the putative new retrovirus (es) and EBV have any causal relationship to MS is still not known, but the findings support this possibility.
 None
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: cell line, protein, RNA, DNA, cell type 
Text: {0} 
Answer:
 None