join  -t '\t' -a1 -1 16 -2 2  PTCL_All.txt Cosmic_Counts_By_Gene.txt 
join: illegal tab character specification
<\code>

or 
<code>join  -t '<tab>' -a1 -1 16 -2 2   PTCL_All.txt Cosmic_Counts_By_Gene.txt 
join: illegal tab character specification