diff --git a/rest-api/src/main/java/lcsb/mapviewer/api/projects/overlays/OverlayRestImpl.java b/rest-api/src/main/java/lcsb/mapviewer/api/projects/overlays/OverlayRestImpl.java
index 5170e23099f3f9f51521dd65225dee123462db69..3318c8b2149af9a7244c030dcaec8d8ad39d1c30 100644
--- a/rest-api/src/main/java/lcsb/mapviewer/api/projects/overlays/OverlayRestImpl.java
+++ b/rest-api/src/main/java/lcsb/mapviewer/api/projects/overlays/OverlayRestImpl.java
@@ -5,6 +5,7 @@ import java.io.IOException;
 import java.io.InputStream;
 import java.nio.charset.StandardCharsets;
 import java.util.ArrayList;
+import java.util.LinkedHashMap;
 import java.util.List;
 import java.util.Map;
 import java.util.TreeMap;
@@ -141,7 +142,7 @@ public class OverlayRestImpl extends BaseRestImpl {
     if (columns != null && !columns.trim().isEmpty()) {
       columnSet = columns.split(",");
     } else {
-      columnSet = new String[] { "modelId", "value", "color", "idObject" };
+      columnSet = new String[] { "modelId", "idObject", "value", "color", "uniqueId" };
     }
     List<Map<String, Object>> result = new ArrayList<>();
 
@@ -378,7 +379,8 @@ public class OverlayRestImpl extends BaseRestImpl {
     if (columns != null && !columns.trim().isEmpty()) {
       columnSet = columns.split(",");
     } else {
-      columnSet = new String[] { "modelId", "value", "color", "idObject", "description", "type", "geneVariations" };
+      columnSet = new String[] { "modelId", "idObject", "value", "color", "description", "type", "geneVariations",
+          "uniqueId" };
     }
     Map<String, Object> result = new TreeMap<>();
     if (ElementIdentifierType.ALIAS.getJsName().equals(elementType)) {
@@ -400,15 +402,16 @@ public class OverlayRestImpl extends BaseRestImpl {
 
   private Map<String, Object> overlayContentToMap(Pair<? extends BioEntity, ColorSchema> bioEntityDataOverlay,
       String[] columns) {
-    Map<String, Object> result = new TreeMap<>();
+    Map<String, Object> result = new LinkedHashMap<>();
     BioEntity bioEntity = bioEntityDataOverlay.getLeft();
     ColorSchema colorSchema = bioEntityDataOverlay.getRight();
     for (String string : columns) {
       String column = string.toLowerCase();
       Object value = null;
-      if (column.equals("id") || column.equals("idobject")) {
-        value = bioEntity.getId();
-      } else if (column.equals("modelId")) {
+      if (column.equals("id") || column.equals("idobject") || column.equals("uniqueid")) {
+        //casting to string is only to provide the same results as before refactoring
+        value = bioEntity.getId()+"";
+      } else if (column.equals("modelid")) {
         value = bioEntity.getModel().getId();
       } else if (column.equals("value")) {
         value = colorSchema.getValue();