diff --git a/Assets/VRM/UniGLTF/Editor/UniGLTFTests.cs b/Assets/VRM/UniGLTF/Editor/UniGLTFTests.cs
index a2b9de381..b9d567742 100644
--- a/Assets/VRM/UniGLTF/Editor/UniGLTFTests.cs
+++ b/Assets/VRM/UniGLTF/Editor/UniGLTFTests.cs
@@ -575,6 +575,26 @@ namespace UniGLTF
             Assert.AreEqual("[version.String] null", ex.Message);
         }
 
+        [Test]
+        public void GLTFTest()
+        {
+            var model = new glTF()
+            {
+                asset = new glTFAssets()
+                {
+                    version = "0.49",
+                },
+                extensions = null,
+            };
+
+            var c = new JsonSchemaValidationContext("")
+            {
+                EnableDiagnosisForNotRequiredFields = true,
+            };
+            var json2 = JsonSchema.FromType<glTF>().Serialize(model, c);
+            Assert.AreEqual(@"{""asset"":{""version"":""0.49""},""extras"":{}}", json2);
+        }
+
         [Test]
         public void SameMeshButDifferentMaterialExport()
         {
diff --git a/Assets/VRM/UniGLTF/Scripts/Format/glTF.cs b/Assets/VRM/UniGLTF/Scripts/Format/glTF.cs
index 7df4bd651..17252adbb 100644
--- a/Assets/VRM/UniGLTF/Scripts/Format/glTF.cs
+++ b/Assets/VRM/UniGLTF/Scripts/Format/glTF.cs
@@ -31,7 +31,7 @@ namespace UniGLTF
         public glTFAssets asset = new glTFAssets();
 
         #region Buffer
-        [JsonSchema(MinItems = 1)]
+        [JsonSchema(MinItems = 1, ExplicitIgnorableItemLength = 0)]
         public List<glTFBuffer> buffers = new List<glTFBuffer>();
         public int AddBuffer(IBytesBuffer bytesBuffer)
         {
@@ -40,7 +40,7 @@ namespace UniGLTF
             return index;
         }
 
-        [JsonSchema(MinItems = 1)]
+        [JsonSchema(MinItems = 1, ExplicitIgnorableItemLength = 0)]
         public List<glTFBufferView> bufferViews = new List<glTFBufferView>();
         public int AddBufferView(glTFBufferView view)
         {
@@ -49,7 +49,7 @@ namespace UniGLTF
             return index;
         }
 
-        [JsonSchema(MinItems = 1)]
+        [JsonSchema(MinItems = 1, ExplicitIgnorableItemLength = 0)]
         public List<glTFAccessor> accessors = new List<glTFAccessor>();
 
         T[] GetAttrib<T>(glTFAccessor accessor, glTFBufferView view) where T : struct
@@ -212,7 +212,7 @@ namespace UniGLTF
             return samplers[index];
         }
 
-        [JsonSchema(MinItems = 1)]
+        [JsonSchema(MinItems = 1, ExplicitIgnorableItemLength = 0)]
         public List<glTFImage> images = new List<glTFImage>();
 
         public int GetImageIndexFromTextureIndex(int textureIndex)