diff --git a/src/render.ts b/src/render.ts
index b7c66f3c..3860223b 100644
--- a/src/render.ts
+++ b/src/render.ts
@@ -174,6 +174,13 @@ const setValue = <T extends HTMLElement>(element: T, propertyKey: PropertyKey, v
  */
 const isListenerProperty = (propertyKey: string): propertyKey is `on${string}` => propertyKey[0] === 'o' && propertyKey[1] === 'n';
 
+/**
+ * Check if an item is in a list.
+ * @param items List of child nodes.
+ * @param item The item to check.
+ */
+const contains = <T>(items: T[], item: T) => ([] as typeof items).indexOf.call(items, item) !== -1;
+
 /**
  * Render a set of Nodes into another, with some checks for Nodes in order to avoid
  * useless changes in the tree and to mantain or update the state of compatible Nodes.
@@ -259,7 +266,7 @@ export const internalRender = (
                 }
 
                 const renderFragmentContext = getOrCreateContext(placeholder);
-                const isAttached = () => fragments.indexOf(renderFragmentContext) !== -1;
+                const isAttached = contains.bind(null, fragments, renderFragmentContext);
                 let running = true;
                 const requestUpdate: UpdateRequest = renderFragmentContext.requestUpdate = () => {
                     if (renderFragmentContext.requestUpdate !== requestUpdate) {
@@ -458,7 +465,7 @@ export const internalRender = (
                         const oldClasses = convertClasses(oldProperties.class);
                         for (let i = 0, len = oldClasses.length; i < len; i++) {
                             const className = oldClasses[i];
-                            if (newClasses.indexOf(className) === -1) {
+                            if (contains(newClasses, className)) {
                                 classList.remove(className);
                             }
                         }
@@ -492,7 +499,7 @@ export const internalRender = (
                     const Component = template.Component;
                     if (type === 'string') {
                         const observedAttributes = Component.observedAttributes;
-                        if (!observedAttributes || observedAttributes.indexOf(propertyKey) === -1) {
+                        if (!observedAttributes || contains(observedAttributes, propertyKey)) {
                             const descriptor = (propertyKey in templateElement) && getPropertyDescriptor(templateElement, propertyKey);
                             if (!descriptor || !descriptor.get || descriptor.set) {
                                 setValue(templateElement, propertyKey, value);
@@ -585,7 +592,7 @@ export const internalRender = (
         // now, we are confident that if the input is a Node or a Component,
         // check if Nodes are the same instance
         // (patch result should return same Node instances for compatible types)
-        if (templateNode.parentNode === root) {
+        if (contains(childNodes, templateNode)) {
             while (templateNode !== currentNode) {
                 DOM.removeChild(root, currentNode, slot);
                 currentNode = childNodes.item(currentIndex) as Node;
diff --git a/test/render.spec.js b/test/render.spec.js
index 9f560f70..acd8e8be 100644
--- a/test/render.spec.js
+++ b/test/render.spec.js
@@ -219,23 +219,43 @@ describe('render', function() {
         });
 
         it('should update nodes', () => {
-            DNA.render(DNA.h('ul', { class: 'list' }, DNA.h('li', null, 'One'), DNA.h('li', null, 'Two'), DNA.h('li', null, 'Three'), DNA.h('li', null, 'Four')), wrapper);
+            DNA.render(DNA.h('ul', { class: 'list' },
+                DNA.h('li', null, 'One'),
+                DNA.h('li', null, 'Two'),
+                DNA.h('li', null, 'Three'),
+                DNA.h('li', null, 'Four'),
+                DNA.h('li', null, 5),
+                DNA.h('li', null, '6')
+            ), wrapper);
             const list = wrapper.querySelector('ul.list');
             const children = list.childNodes;
             expect(children[0].textContent).to.be.equal('One');
             expect(children[1].textContent).to.be.equal('Two');
             expect(children[2].textContent).to.be.equal('Three');
             expect(children[3].textContent).to.be.equal('Four');
-            DNA.render(DNA.h('ul', { class: 'list' }, DNA.h('li', null, 'Five'), DNA.h('li', null, 'Six'), DNA.h('li', null, 'Seven'), DNA.h('li', null, 'Height')), wrapper);
+            expect(children[4].textContent).to.be.equal('5');
+            expect(children[5].textContent).to.be.equal('6');
+            DNA.render(DNA.h('ul', { class: 'list' },
+                DNA.h('li', null, 'Seven'),
+                DNA.h('li', null, 'Eight'),
+                DNA.h('li', null, 'Nine'),
+                DNA.h('li', null, 'Ten'),
+                DNA.h('li', null, 11),
+                DNA.h('li', null, 12)
+            ), wrapper);
             const newChildren = list.childNodes;
             expect(children[0]).to.be.equal(newChildren[0]);
             expect(children[1]).to.be.equal(newChildren[1]);
             expect(children[2]).to.be.equal(newChildren[2]);
             expect(children[3]).to.be.equal(newChildren[3]);
-            expect(children[0].textContent).to.be.equal('Five');
-            expect(children[1].textContent).to.be.equal('Six');
-            expect(children[2].textContent).to.be.equal('Seven');
-            expect(children[3].textContent).to.be.equal('Height');
+            expect(children[4]).to.be.equal(newChildren[4]);
+            expect(children[5]).to.be.equal(newChildren[5]);
+            expect(children[0].textContent).to.be.equal('Seven');
+            expect(children[1].textContent).to.be.equal('Eight');
+            expect(children[2].textContent).to.be.equal('Nine');
+            expect(children[3].textContent).to.be.equal('Ten');
+            expect(children[4].textContent).to.be.equal('11');
+            expect(children[5].textContent).to.be.equal('12');
         });
 
         it('should update add and remove attributes', () => {