How can I change the JavaScript code?

Question

// Update the radius when the user makes a selection.
google.maps.event.addDomListener(document.getElementById('radius'),
    'change', function() {
       var meters = parseInt(this.value, 10);
       layer.setOptions({
         query: {
           select: locationColumn,
           from: tableId,
           where: 'ST_INTERSECTS(Latitude, ' +
               'CIRCLE(LATLNG(53.337638, -6.266971), ' + meters + '))'
          }
       });
       circle.setRadius(meters);
       //alert(position);
       //circle.setCenter(new google.maps.LatLng(position));
});

I want to change the (53.337638, -6.266971) to be a varible 'position', position has the same value type with (x,y), but it doesn't work with where: 'ST_INTERSECTS(Latitude, ' + 'CIRCLE(LATLNG('+position+'), ' + meters + '))' How can I modify the code ?