I am trying to sum taxa per participant in this partial of a dataset.
In the first column there are repeating taxa, the other columns are participants and counts of the taxa. 
When I had only one person, I used the =SUMIF($A$2:$A$15, E2, $B$2:$B$15) function after removing duplicates in excel which did the trick. 
I am trying to avoid having to do it 150 times for each participant. Would anyone have an idea, either in Excel or R?
Taxon                  A              B          C                 D
 Bacteroides    193,568     30,950     114,136  390,546
 Prevotella     0               364,092    0                  0
 Bacteroides    352,626     389,938 8,492   213,736
 Fusicatenibacter   669,374 402,290 317,594 178,340
 Bacteroides    563,284      14,114 832,400 30,958
 Bacteroides        0                     0           0          78,302
 Agathobacter     204,810       117,144 180,104 69,296
 Alistipes               0                136,800     0            8,430
 Blautia              161,132        261,660      9,092 118,602
 Ruminococcus  75,010             0           282   26,368
 Bacteroides       50,782         23,066    61,236  37,214
 Prevotella    91,560              0             19,676 69,752
 Blautia              125,734              0            26,750  93,874
 Alistipes        139,518         51,154    87,490   5,266
 Agathobacter      4,854          13,830    34,772   1,782
How do you know which duplicate taxon to remove?
I remove all duplicates, then sum counts with the SUMIF function in excel. Works for one participant/column and I am looking for a formula which does it for all columns.