diff --git a/src/nf_modules/gatk4/main.nf b/src/nf_modules/gatk4/main.nf
index e616741fa0c3ea96335a1c3b71cbb04e9a76f84e..f0b13262b71a4e6e9f5076ead438f6fab256f803 100644
--- a/src/nf_modules/gatk4/main.nf
+++ b/src/nf_modules/gatk4/main.nf
@@ -261,7 +261,7 @@ process personalized_genome {
 gatk --java-options "-Xmx${xmx_memory}" -T FastaAlternateReferenceMaker\
   -R ${reference} \
   -V ${vcf} \
-  -o ${file_id.library}_genome.fasta
+  -o ${file_id[0]}_genome.fasta
 """
 }