Validating Radio Buton Clearing the Selected value by clicking clear button using Java Script

<table>
 <tr>
    <td><asp:Label ID="lblGender" runat="server" Text="Gender"></asp:Label></td>
    <td style="width: 197px">
    <asp:RadioButtonList ID="rblGender" runat="server" RepeatDirection="Horizontal">
    <asp:ListItem Text="Male" Value="1"></asp:ListItem>
    <asp:ListItem Text="Female" Value="2"></asp:ListItem>
    </asp:RadioButtonList>
    </td>
    </tr>
</table>

<script language="javascript" type="text/javascript">
 function Validate()
  { 
   var Gender=document.getElementById("rblGender");
   var flag=0;
  for(i=0;i<Gender.cells.length;i++)
   {
   if(Gender.cells[i].firstChild.checked)
   {
   flag=1;
   break;
   }
   }
  if(flag==0)
   {
   alert("Please choose gender");
   return false;
   }
  }

function Clear()
   {
     var Gender=document.getElementById("rblGender");
     for(var i=0;i<rblGender.cells.length;i++)
   {
   if(Gender.cells[i].firstChild.checked)
   {
   Gender.cells[i].firstChild.checked=false;
   }
   }
   }

Page_load()
{
        btnSubmit.Attributes.Add("onClick", "return Validate()");
        btnClear.Attributes.Add("onClick", "Clear()");
}