Change post/article microdata to Article

functions.php

<?php
//  functions.php

add_filter( 'genesis_attr_entry', 'custom_genesis_attr_entry' );
/**
 * Callback for Genesis 'genesis_attr_entry' filter.
 * 
 * Change the current entry's 'itemprop' and 'itemtype' attributes to 
 * use the Article microdata schema from BlogPosting.
 * 
 * @package Genesis 2.0
 * @category Markup
 * @author Ryan Meier http://www.rfmeier.net/
 * 
 * @global $post $post The current post object
 * @param array $attributes Array of attributes
 * @return array $attributes Array of attributes
 */
function custom_genesis_attr_entry( $attributes ){
	
	// change itemprop attribute
	$attributes['itemprop']  = 'articleBody';

	// change itemtype attribute
	$attributes['itemtype']  = 'http://schema.org/Article';
	
	// return the attributes
	return $attributes;
	
}