Considering that what you basically do is finding lines that start with 'Hox', why don't you just do: 
    $ grep ^Hox MOUSE_TF1.txt > HOX_GENE_TF.txt

[download]
If the reordering of the columns is essential, you can always pipe the output of grep through col.

In reply to Re: If Statements and Regular Expressions by JavaFan
in thread If Statements and Regular Expressions by TempAcolyte

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