diff --git a/packages/core/src/hook/useSx.test.ts b/packages/core/src/hook/useSx.test.ts
index 96ed9ac..106f49b 100644
--- a/packages/core/src/hook/useSx.test.ts
+++ b/packages/core/src/hook/useSx.test.ts
@@ -74,6 +74,12 @@ const baseTheme: ThemedDict = {
       fontStyle: 'normal',
       fontWeight: '400',
     },
+    body: {
+      fontFamily: 'Noto Sans',
+      fontSize: 12,
+      fontStyle: 'normal',
+      fontWeight: '400',
+    },
   },
 };
 
@@ -241,6 +247,23 @@ describe('style parse priority', () => {
       { fallback: { width: 1, marginX: 5 }, expectation: { width: 2, marginHorizontal: 4 } },
     );
   });
+
+  it('sx typography > fallback', () => {
+    expectResult(
+      baseTheme,
+      { t: 'title' },
+      {
+        fallback: { typography: 'body' },
+        expectation: {
+          fontFamily: 'Noto Sans',
+          fontSize: 14,
+          fontStyle: 'normal',
+          fontWeight: '400',
+        },
+        styleType: 'TextStyle',
+      },
+    );
+  });
 });
 
 describe('radii', () => {
diff --git a/packages/core/src/internal/util/mutateShortcutPropToOriginalKeys.ts b/packages/core/src/internal/util/mutateShortcutPropToOriginalKeys.ts
index 35d838a..4e0ac82 100644
--- a/packages/core/src/internal/util/mutateShortcutPropToOriginalKeys.ts
+++ b/packages/core/src/internal/util/mutateShortcutPropToOriginalKeys.ts
@@ -6,13 +6,15 @@ export function mutateShortcutPropToOriginalKeys(sx?: TextSxProps | null) {
     return sx;
   }
 
+  const ret = { ...sx };
+
   for (const key of Object.keys(sx)) {
     if (SHORTCUT_NAME_MAP[key]) {
-      if (!(SHORTCUT_NAME_MAP[key] in sx)) {
-        sx[SHORTCUT_NAME_MAP[key]] = sx[key];
+      if (!(SHORTCUT_NAME_MAP[key] in ret)) {
+        ret[SHORTCUT_NAME_MAP[key]] = sx[key];
       }
     }
   }
 
-  return sx;
+  return ret;
 }