diff --git a/environment.yml b/environment.yml
index 0aa5ce6..827eea3 100644
--- a/environment.yml
+++ b/environment.yml
@@ -7,7 +7,7 @@ dependencies:
   - biopython>=1.78
   - prodigal>=2.6.3
   - diamond>=2.0.14
-  - blast>=2.12.1
+  - blast>=2.12.0
   - hmmer>=3.3.1
   - infernal>=1.1.4
   - mummer4>=4.0.0beta2
\ No newline at end of file
diff --git a/platon/utils.py b/platon/utils.py
index a525609..fe53812 100644
--- a/platon/utils.py
+++ b/platon/utils.py
@@ -25,7 +25,7 @@ def print_version(self):
 DEPENDENCIES = [  # List of dependencies: tuples for: min version, max version, tool name & command line parameter, dependency check exclusion options
     (Version(2,6,3), Version(VERSION_MAX_DIGIT, VERSION_MAX_DIGIT, VERSION_MAX_DIGIT), VERSION_REGEX, ('prodigal', '-v')),
     (Version(2,0,14), Version(VERSION_MAX_DIGIT, VERSION_MAX_DIGIT, VERSION_MAX_DIGIT), VERSION_REGEX, ('diamond', 'help')),
-    (Version(2,12,1), Version(VERSION_MAX_DIGIT, VERSION_MAX_DIGIT, VERSION_MAX_DIGIT), VERSION_REGEX, ('blastn', '-version')),
+    (Version(2,12,0), Version(VERSION_MAX_DIGIT, VERSION_MAX_DIGIT, VERSION_MAX_DIGIT), VERSION_REGEX, ('blastn', '-version')),
     (Version(3,3,1), Version(VERSION_MAX_DIGIT, VERSION_MAX_DIGIT, VERSION_MAX_DIGIT), VERSION_REGEX, ('hmmsearch', '-h')),
     (Version(4,0,0), Version(VERSION_MAX_DIGIT, VERSION_MAX_DIGIT, VERSION_MAX_DIGIT), VERSION_REGEX, ('nucmer', '-V')),
     (Version(1,1,2), Version(VERSION_MAX_DIGIT, VERSION_MAX_DIGIT, VERSION_MAX_DIGIT), VERSION_REGEX, ('cmscan', '-h'))