So this is a wonderful web page that was pointed out to me the other day! I have 2 files that I would like to combine. File 1 contains: chrno,marker,homozygotes,rare,observed,expected,pvalue,af 01,rs11206709,714,6,178,169,0.2147,Cases 01,rs11206709,746,11,158,162,0.4557,Controls 01,rs11206709,1457,17,336,331,0.7017,Unrelated 06,rs734560,504,52,388,356,0.0092,Cases 06,rs734560,550,96,354,381,0.0332,Controls 06,rs734560,1053,147,740,735,0.8629,Unrelated 04,rs7659192,685,16,206,206,1.0000,Cases 04,rs7659192,697,21,206,213,0.2611,Controls 04,rs7659192,1378,37,413,420,0.4214,Unrelated File 2 contains counts of inheritance inconsistencies: 01,rs10157092,1 01,rs10157835,2 01,rs10429923,1 01,rs10493696,1 01,rs10494391,1 01,rs10495114,1 01,rs10733060,1 01,rs10753515,1 01,rs1075364,2 File 1 contains 952,185 lines minus header and File 2 contains 7632. The majority of the markers don't have an inconsistency. I would like to merge these files together by marker and have File 1 contain a new column of counts of inheritance inconsistencies. I tried using the merge command with $col1=1 but got an empty output file. Thanks very much in advance, Peggy White 5/24