How to complete a test order form for whole genome sequencing

What is a test order form?

A test order form (TOF) is the request form completed by a clinician that accompanies the patient’s sample to the laboratory for testing. It contains information about the patient, their phenotype and which test is required.

There is a special TOF for ordering whole genome sequencing (WGS), as opposed to general genomic tests. You can find all these forms on your local Genomic Laboratory Hub (GLH) website – direct links below. In most cases, you can complete the form digitally.

What is the structure?

Most test order forms will have the following sections:

patient demographics;
clinical information;
test request;
family members to be tested;
samples;
clinician details; and
patient phenotype (Human Phenotype Ontology terms).

These sections are explained below.

How do I complete the form?

Each section of the form will need to be completed as explained below.

Section	Description
Patient demographics	Ensure this section is completed as comprehensively as possible. It is important to include the sex and ethnicity of the patient, as this may impact how a result is interpreted. In this section, you are also required to select whether the test is a singleton (you are just testing one person) or a trio (you are testing three people, usually a proband and their parents).
Clinical information	Please include a summary of relevant information about the patient’s phenotype and family history. This may include: clinical features of the patient; history of genetic disease in the family, including name of condition and how that person is related to your patient; any relevant negative testing, such as an array, and/or any variants of uncertain significance that have been detected through previous genetic analysis; and the specific genomic variant in a family member, including where they were tested, if known. You must ensure that all relevant clinical information is included. If something important is missed, plausible genetic variants could be discounted and the results could be incorrect.
Test request	If the test is clinically urgent, you need to make it clear in this section. It is important to highlight the reasons for the urgency and to liaise with the laboratory to ensure prompt processing of any samples. Every genomic test currently available to request is in the National Genomic Test Directory. Each test is organised into clinical specialties and allocated a specific code (R number). To ascertain the correct test, you will need to: peruse the National Genomic Test Directory; ensure that you are eligible to request this test (in the ‘Requesting specialty’ section); ensure the patient fulfils the testing criteria; and identify the R number, which is at the top of each page, and record this in the TOF. In some cases, multiple tests may be requested from one sample. There is a section for you to include the R numbers of any additional panels. This includes a link to PanelApp, a resource containing a list of panels available through the test directory and the genes that each includes. You also need to ensure that the proband’s age of onset is included. If there is any suspicion of incomplete penetrance, this should also be highlighted to aid with interpretation. There is also a section to complete should you have a suspicion of a specific condition or if any disease has been confirmed.
Family members to be tested	In some cases (such as a trio whole genome sequencing test), more than one person will require testing as part of one request. You must ensure that these people’s details are recorded on the TOF, including their demographics, relationship to proband and details about their samples.
Samples	If your GLH uses a separate sample form, you do not need to fill out the samples section. Otherwise, you should complete these details as fully as possible. It is important to ensure that you are testing the DNA of the patient. If a patient has had a bone marrow transplant, for example, their blood DNA (extracted from lymphocytes) will actually be that of the donor. In such cases, it is essential that a pre-transplant DNA sample is submitted, or a different type of tissue is used, such as fibroblasts obtained from a skin biopsy.
Clinician details	The details of the person completing the form and the person with overall clinical responsibility for the patient should be noted.
Patient phenotype	On the second page of the form, you will be expected to enter information about the proband’s phenotype and whether these features are present in the other family members you are testing. You need to complete this section using HPO terms. As always, it is important to ensure that you have captured the phenotype as fully as possible using the most specific HPO term that is appropriate.

What if I have a question?

In most cases, your local GLH will be able to assist with any queries. In some cases, your local clinical genetics team may be able to provide advice. Guidance should be sought in accordance with the clinical urgency of the test in question.

I have completed the TOF. What next?

The completed TOF should be sent to the testing laboratory along with the patient sample(s). You must also ensure that you have completed a record of discussion form and that this is filed in the patient’s records.

Key messages

The TOF for WGS is different from other test order forms and can usually be completed digitally.
All sections of the form should be completed thoroughly and legibly.
Your local GLH is best placed to advise on any queries that you might have.

Resources

For clinicians

Genomics England: NHS Genomic Medicine Service (GMS) Signed Off Panels Resource
NHS England: Genomic Laboratory Hubs
NHS England: National Genomic Test Directory
NHS England Genomics Education Programme: Requesting whole genome sequencing: Information for clinicians