Here is a simple way to customize the output of the Author Box in the Genesis theme framework. Just drop this into your child theme's functions.php file and adjust the $pattern as desired.

functions.php

<?php
// Don't copy the opening php tag above

add_filter( 'genesis_author_box', 'wsm_author_box_pattern' );
function wsm_author_box_pattern( $pattern ) {
	
	$gravatar = get_avatar(get_the_author_id() , 80);
	$author = get_the_author_meta( 'display_name' );
	$description = get_the_author_meta( 'description' );
	
	$pattern  = sprintf( '<section %s>', genesis_attr( 'author-box' ) );
	$pattern .= $gravatar . '<h3 class="author-box-title">About ' . $author . '</h3><div class="author-box-content" itemprop="description">' . $description . '</div>';
	$pattern .= '</section>';
	
	return $pattern;
	
}