A non perl solution:
intersection: 
grep -w -f gene_list1 gene_list2

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unique in the second list for e.g: 
grep -v -f gene_list1 gene_list2

[download]
NOTE: If the file size are large, this may not work!

In reply to Re: Common between two lists by umasuresh
in thread Common between two lists by perllearner007

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