1.0Glossaryhttps://www.healthbenefitstimes.com/glossaryGlossaryhttps://www.healthbenefitstimes.com/glossary/author/adminglossary/rich600338<blockquote class="wp-embedded-content" data-secret="zuTLnIneDX"><a href="https://www.healthbenefitstimes.com/glossary/trisomy-18/">Trisomy 18</a></blockquote><iframe sandbox="allow-scripts" security="restricted" src="https://www.healthbenefitstimes.com/glossary/trisomy-18/embed/#?secret=zuTLnIneDX" width="600" height="338" title="“Trisomy 18” — Glossary" data-secret="zuTLnIneDX" frameborder="0" marginwidth="0" marginheight="0" scrolling="no" class="wp-embedded-content"></iframe><script> /*! This file is auto-generated */ !function(d,l){"use strict";l.querySelector&&d.addEventListener&&"undefined"!=typeof URL&&(d.wp=d.wp||{},d.wp.receiveEmbedMessage||(d.wp.receiveEmbedMessage=function(e){var t=e.data;if((t||t.secret||t.message||t.value)&&!/[^a-zA-Z0-9]/.test(t.secret)){for(var s,r,n,a=l.querySelectorAll('iframe[data-secret="'+t.secret+'"]'),o=l.querySelectorAll('blockquote[data-secret="'+t.secret+'"]'),c=new RegExp("^https?:$","i"),i=0;i<o.length;i++)o[i].style.display="none";for(i=0;i<a.length;i++)s=a[i],e.source===s.contentWindow&&(s.removeAttribute("style"),"height"===t.message?(1e3<(r=parseInt(t.value,10))?r=1e3:~~r<200&&(r=200),s.height=r):"link"===t.message&&(r=new URL(s.getAttribute("src")),n=new URL(t.value),c.test(n.protocol))&&n.host===r.host&&l.activeElement===s&&(d.top.location.href=t.value))}},d.addEventListener("message",d.wp.receiveEmbedMessage,!1),l.addEventListener("DOMContentLoaded",function(){for(var e,t,s=l.querySelectorAll("iframe.wp-embedded-content"),r=0;r<s.length;r++)(t=(e=s[r]).getAttribute("data-secret"))||(t=Math.random().toString(36).substring(2,12),e.src+="#?secret="+t,e.setAttribute("data-secret",t)),e.contentWindow.postMessage({message:"ready",secret:t},"*")},!1)))}(window,document); //# sourceURL=https://www.healthbenefitstimes.com/glossary/wp-includes/js/wp-embed.min.js </script> Trisomy 18 or Edwards syndrome, named for the researcher who first identified it, is an autosomal dominant chromosome ab¬ normality. The autosomes are the 22 pairs of non-sex chromosomes. A dominant gene is a gene that overrides the normal copy from the partner and has a 50% chance of being passed on. There are three types of Trisomy 18. In the full form, every cell in the body has three number 18 chromosomes instead of the normal pair. With the mosaic form, there is a mixture of abnormal cells (three number 18 chromosomes) and normal cells (pairs of number 18 chromosomes). In the third condition (partial form), either the long arm (18q+) or the short arm (18p+) of Chromosome 18 is duplicated.