Cannot read property 'checked' of undefined React

I'm making a litte app(a list of topics) where i use checkbox to delete some topic but when i start the app the console said "Cannot read property 'checked' of undefined" i read on some post that it could be cause i rewrite the check box bur i don't see where.

can you help ?

import React, { Component, PropTypes } from 'react';
import { createContainer } from 'meteor/react-meteor-data';
import { Topics } from '../api/topic.js';
import Topic from './Topic.jsx';

class AppTopic extends Component {

  toggleChecked() {
      // Set the checked property to the opposite of its current value
      Topics.update(this.props.topic._id, {
        $set: { checked: !this.props.topic.checked },
      });
    }

    deleteThisTopic() {
      Topics.remove(this.props.topic._id);
    }

  renderTopics() {
    return this.props.topics.map((topic) => (
      <Topic key={topic._id} topic={topic} />
    ));
  }

  render() {

    // Give tasks a different className when they are checked off,
    // so that we can style them nicely in CSS
    const topicClassName = this.props.topic.checked ? 'checked' : '';

      return (

        <li className={topicClassName}>
        <button className="delete" onClick={this.deleteThisTopic.bind(this)}>
          &times;
        </button>

        <input
          type="checkbox"
          readOnly
          checked={this.props.topic.checked}
          onClick={this.toggleChecked.bind(this)}
        />
        <span className="text">{this.renderTopics()}</span>
      </li>
      );

    }
  }

  AppTopic.propTypes = {
  topics: PropTypes.array.isRequired
};


export default createContainer(() => {
  return {
    topics: Topics.find({}).fetch(),
  };
}, AppTopic);