9721
The visualization of heavy and light chain genes in B-lymphoid cells showed that the three Ig genes are differentially and nonrandomly distributed in different nuclear subvolumes: the kappa genes were found to be preferentially confined to an outer nuclear volume, whereas the gamma and lambda genes consistently occupied more central positions within the nucleus , the lambda genes being more interior when compared with the gamma genes .
 ( DNA: lambda genes, None) , ( DNA: Ig genes, None) , ( DNA: gamma genes, None) , ( DNA: kappa genes, None) , ( cell type: B-lymphoid cells, None) 
Locate the role in the text that participated in the event based on the event type and return it in the event list. 
 Option: Event type: RNA,cell type,protein,cell line,DNA, Arguments type: . 
Text: {0} 
Answer:
 ( DNA: lambda genes, None) , ( DNA: Ig genes, None) , ( DNA: gamma genes, None) , ( DNA: kappa genes, None) , ( cell type: B-lymphoid cells, None) 