diff --git a/containers/celltypist/context/main.py b/containers/celltypist/context/main.py
index 375bb8f..afac137 100644
--- a/containers/celltypist/context/main.py
+++ b/containers/celltypist/context/main.py
@@ -62,7 +62,7 @@ def normalize_var_names(
         names = data.var_names
 
         def getNewName(name: str):
-            (key,) = name.split(".", 1)
+            key = name.split(".", 1)[0]
             return lookup.get(key, name)
 
         data.var_names = t.cast(t.Any, names.map(getNewName))