diff --git a/gatk.wdl b/gatk.wdl
index cc8f830f29f16edf74f91df2f5655406ebd855c0..0ab30fc18de79b75e53ece5ba4ae3e768f3436ca 100644
--- a/gatk.wdl
+++ b/gatk.wdl
@@ -109,7 +109,7 @@ task CombineGVCFs {
     command {
         set -e
         mkdir -p $(dirname ~{outputPath})
-        gatk --java-options -Xmx~{javaXmx}G \
+        gatk --java-options -Xmx~{javaXmx} \
         CombineGVCFs \
         -R ~{referenceFasta} \
         -O ~{outputPath} \