diff --git a/workflow/rules/common.smk b/workflow/rules/common.smk
index ec08d00..1dc6a6b 100644
--- a/workflow/rules/common.smk
+++ b/workflow/rules/common.smk
@@ -104,7 +104,7 @@ def get_plot_cov_labels():  # TODO check if ever used anywhere
 
 def get_truth_url(wildcards, input):
     genome = genomes[wildcards.genome]
-    truth = genome["truth"][get_genome_build(wildcards)]
+    truth = genome["truth"][get_genome_build()]
     if isinstance(truth, dict):
         truth = truth[wildcards.truthset]
     if input.archive:
@@ -116,7 +116,7 @@ def get_truth_url(wildcards, input):
 def get_truthsets(csi=False):
     def inner(wildcards):
         genome = genomes[wildcards.genome]
-        truthsets = genome["truth"][get_genome_build(wildcards)]
+        truthsets = genome["truth"][get_genome_build()]
         if csi:
             return expand(
                 "resources/variants/{genome}/{truthset}.truth.bcf.csi",
@@ -147,8 +147,11 @@ def get_confidence_bed_cmd(wildcards, input):
         return f"curl --insecure -L {bed} {unpack_cmd}"
 
 
-def get_genome_build(wildcards):
-    return config["variant-calls"][wildcards.callset]["genome-build"]
+def get_genome_build():
+    if config.get("grch37"):
+        return "grch37"
+    else:
+        return "grch38"
 
 
 def get_io_prefix(getter):