Hello monks, I have an input file like this: 
chr1 12345 34567 gene1 
chr1 12345 34567 gene2

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I would like to remove duplicate lines when column 1,2 and 3 are the same concatenating column 4. This is the output I would like to have: 
chr1 12345 34567 gene1,gene2

[download]
Can you help me? Thanks!

In reply to Duplicate removal by perl_paduan

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