diff --git a/flexiprep/src/main/scala/nl/lumc/sasc/biopet/pipelines/flexiprep/Cutadapt.scala b/flexiprep/src/main/scala/nl/lumc/sasc/biopet/pipelines/flexiprep/Cutadapt.scala
index ea328d973ba919fbfe2e59164d325aeb7b6969c4..54d80126bfcd1e6a3f6ef60187ed8bff4d6ffd58 100644
--- a/flexiprep/src/main/scala/nl/lumc/sasc/biopet/pipelines/flexiprep/Cutadapt.scala
+++ b/flexiprep/src/main/scala/nl/lumc/sasc/biopet/pipelines/flexiprep/Cutadapt.scala
@@ -38,7 +38,7 @@ class Cutadapt(root: Configurable, fastqc: Fastqc) extends nl.lumc.sasc.biopet.e
       (fastqc.foundAdapters ++ customAdapters)
         .map(adapter => adapter.seq -> adapter.name).toMap
     } else {
-      Map.empty ++ customAdapters.map(adapter => adapter.seq -> adapter.name).toMap
+      customAdapters.map(adapter => adapter.seq -> adapter.name).toMap
     }
   }
 
diff --git a/flexiprep/src/main/scala/nl/lumc/sasc/biopet/pipelines/flexiprep/QcCommand.scala b/flexiprep/src/main/scala/nl/lumc/sasc/biopet/pipelines/flexiprep/QcCommand.scala
index e43c4e93ec5ba64d0ea416c8b5e1456f3ff9ebb8..2e9a1fa1967000ef88530546c41de93e7f9a39d8 100644
--- a/flexiprep/src/main/scala/nl/lumc/sasc/biopet/pipelines/flexiprep/QcCommand.scala
+++ b/flexiprep/src/main/scala/nl/lumc/sasc/biopet/pipelines/flexiprep/QcCommand.scala
@@ -107,7 +107,7 @@ class QcCommand(val root: Configurable, val fastqc: Fastqc) extends BiopetComman
       val foundAdapters = if (!cutadapt.ignoreFastqcAdapters) {
         fastqc.foundAdapters.map(_.seq) ++ cutadapt.customAdapters.map(_.seq)
       } else {
-        Seq.empty ++ cutadapt.customAdapters.map(_.seq)
+        cutadapt.customAdapters.map(_.seq)
       }
 
       if (foundAdapters.nonEmpty) {