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Also known as: B27

Test category:

Immunology - Autoimmune

Use of test


A specific variant of the human leukocyte antigen B27, HLA-B*27, is associated with a variety of inflammatory disorders.


The presence of this variant indicates that a person is at increased likelihood of having seronegative arthritis, ankylosing spondylitis, anterior uveitis, iritis, psoriatic arthritis, Reiter's syndrome and Crohn's disease.

The absence of this variant places a person at decreased likelihood of having these disorders, and of having severe manifestations of these disorders.

This is a not a diagnostic test and the result does not prove or exclude a specific clinical diagnosis in an affected person.

Ethical considerations:

This is an assay for heritable variants which can alter the probability that a person will develop a disorder. The test result is not, in isolation, diagnostic of a disease and the test result is not necessarily clinically significant for the patient's relatives.


Analysis of the gene sequence of the HLA-B genes for the presence of this specific variant.

Requesting the test


This test can be requested by any medical practitioner.

Sample required:

4 mL blood in EDTA. Specimens may be collected by the requesting practitioner or at any Sonic Healthcare collection centre (see link below).

To help ensure the quality of the test, a genetic test should be done with a dedicated sample whenever possible i.e. a sample collected specifically for that test rather than a sample that is used for multiple tests.

We recommend that the patient or another adult check the labelling of request forms and sample tubes. 

>Link to Sonic Healthcare collection centres

Turnaround time:

2 business days.


This test has a Medicare rebate which, subject to the requirements of the Medicare descriptor being met, may cover all or part of the cost.


The Medicare details, including descriptor and schedule fee, are listed under MBS item 73320.

Click here for our billing policy.