remove_action( 'genesis_after_post', 'genesis_get_comments_template' );

add_shortcode('test', 'commentsShortCode');

function commentsShortCode() {
  ob_start();
  genesis_get_comments_template();
  $comments= ob_get_clean();
  return $comments;
}

add_action( 'init', 'commentsShortCode' );