diff --git a/src/hgvs/utils/altseqbuilder.py b/src/hgvs/utils/altseqbuilder.py
index 8ae433b9..2d5c474a 100644
--- a/src/hgvs/utils/altseqbuilder.py
+++ b/src/hgvs/utils/altseqbuilder.py
@@ -186,7 +186,7 @@ def _get_variant_region(self):
         ):
             result = self.T_UTR
         elif (
-            self._var_c.posedit.edit.type == "dup"
+            self._var_c.posedit.edit.type in ["dup", "ins"]
             and self._var_c.posedit.pos.end.datum == Datum.CDS_END
         ):
             result = self.T_UTR
diff --git a/tests/data/cache-py3.hdp b/tests/data/cache-py3.hdp
index ff1c19d2..ba089408 100644
Binary files a/tests/data/cache-py3.hdp and b/tests/data/cache-py3.hdp differ
diff --git a/tests/test_hgvs_variantmapper.py b/tests/test_hgvs_variantmapper.py
index 72d9408b..0c003ea5 100644
--- a/tests/test_hgvs_variantmapper.py
+++ b/tests/test_hgvs_variantmapper.py
@@ -118,6 +118,12 @@ def test_map_of_c_out_of_reference_bound(self):
         with pytest.raises(HGVSError, match="coordinate is out of bounds"):
             self.vm.c_to_p(var_c)
 
+    def test_map_of_ins_three_prime_utr(self):
+        hgvs_c = "NM_004985.4:c.567_*1insCCC"
+        var_c = self.hp.parse_hgvs_variant(hgvs_c)
+        var_p = self.vm.c_to_p(var_c)
+        self.assertEqual(str(var_p), "NP_004976.2:p.?")
+
     def test_map_of_dup_three_prime_utr(self):
         hgvs_c = "NM_153223.3:c.2959_*1dup"
         var_c = self.hp.parse_hgvs_variant(hgvs_c)
diff --git a/tests/test_hgvs_variantmapper_cp_sanity.py b/tests/test_hgvs_variantmapper_cp_sanity.py
index 4cc09ca5..e186f744 100644
--- a/tests/test_hgvs_variantmapper_cp_sanity.py
+++ b/tests/test_hgvs_variantmapper_cp_sanity.py
@@ -159,11 +159,16 @@ def test_five_prime_utr(self):
         hgvsp_expected = "MOCK:p.?"
         self._run_conversion(hgvsc, hgvsp_expected)
 
-    def test_three_prime_utr(self):
+    def test_sub_three_prime_utr(self):
         hgvsc = "NM_999999.1:c.*3G>A"
         hgvsp_expected = "MOCK:p.?"
         self._run_conversion(hgvsc, hgvsp_expected)
 
+    def test_ins_three_prime_utr(self):
+        hgvsc = "NM_999999.1:c.39_*1insA"
+        hgvsp_expected = "MOCK:p.?"
+        self._run_conversion(hgvsc, hgvsp_expected)
+
     def test_dup_three_prime_utr(self):
         hgvsc = "NM_999999.1:c.12_*1dup"
         hgvsp_expected = "MOCK:p.?"