JSFiddle - React, Tailwind, and code Playground
HTML
<div id='content'></div>
JavaScript
var $itemVariantRowRadio = $("<input/>")
.attr("type", "radio")
.attr("name", "itemvariant")
.addClass("itemvariant")
.val('whatever');
//$itemVariantRowRadio.attr("checked", true);
$("#content").append($itemVariantRowRadio);
$(".itemvariant").attr('checked', true);