diff --git a/scripts/generate_otu_signifigance_tables_AGP.py b/scripts/generate_otu_signifigance_tables_AGP.py
index d43dc7b..ffab6eb 100755
--- a/scripts/generate_otu_signifigance_tables_AGP.py
+++ b/scripts/generate_otu_signifigance_tables_AGP.py
@@ -266,6 +266,7 @@ def filt_fun(v, i, md):
             if sample_type_prelim in SAMPLE_CONVERTER:
                 sample_type = SAMPLE_CONVERTER[sample_type_prelim]
             elif sample_type in UNKNOWNS:
+                sample_type = 'unknown'
                 sample_time = 'unknown'
             else:
                 sample_type = sample_type_prelim.lower()