Exome Sequencing

Also known as: whole exome sequencing, WES.

What is exome sequencing?

The exome is that part of a child’s whole DNA/genome (the genetic inherited material of an organism) that codes (gives instructions) for the production of proteins. Exome sequencing is a complex laboratory test that involves transcribing all (as opposed to analyzing single genes) of the protein-coding genes in the child’s genome to identify novel disease genes, genetic disorders and/or to confirm disease causing protein variants, without the cost of whole genome sequencing. This technique can be used to determine the genetic cause of many rare genetic disorders that are present at birth.

What happens during the procedure?

A routine sample of blood is drawn from a vein of the child (sometimes cells from other tissues like the lining of the cheek or skin cells, may be used, and sometimes from both parents and/or sibling) and sent to the laboratory for testing.

Is any special preparation needed?

In most cases, no special preparation is needed for the test.

What are the risk factors?

Pain, bleeding, infection, and damage to surrounding organs and tissues are potential risks from blood drawing.

Reviewed by: Jack Wolfsdorf, MD, FAAP

This page was last updated on: March 26, 2019 12:25 PM