accessibility - label attributes for radiobuttons

I have a form which contains a 'gender' label and two radio buttons'male' and 'female'. How can I put 'label for' in this particular scenario ?

<label for="username">User Name</label> <input开发者_StackOverflow type ="text" id="username" />
<label for="?">Gender</label>
    <label for="male"><input type="radio" id="male" value="male" /> </label>
    <label for="female"><input type="radio" id="female" value="female" /> </label>

You do not need a label around Gender, just the male/female ones you have associated with the individual inputs. You could classify Gender either just with a Heading tag or with a Legend tag and a Fieldset spanned around the input collection.

You do however need to output some text in your male/female labels, perhaps after each input.