diff --git a/workflow/main.nf b/workflow/main.nf
index b8179133f26992f78d2e2c33db1a3c606c9b1fce..841516a38fabe1e6a4d8642ef3a1ba8376a8f9db 100644
--- a/workflow/main.nf
+++ b/workflow/main.nf
@@ -132,7 +132,7 @@ process alignReads {
   input:
 
   set sampleId, reads, experimentId, biosample, factor, treatment, replicate, controlId from trimmedReads
-  file index from bwaIndex.distinct()
+  file index from bwaIndex.first()
 
   output: