You can definitely hide it with Javascript, if that's an option, one way would be
<script>
function hideGV(){
document.getElementById('<%=GridView1.ClientID%>').style.display='none';
}
</script>
If rather want to insert the tbody/tr
elements and using jQuery is an option for you, here's an example.
jQuery option to insert tbody/tr
<script>
$(function(){
$('#<%=GridView1.ClientID%>').append('<tbody><tr><td></td></tr></tbody>');
});
</script>