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HLA-A*31:01 Genotype

Published: July 27, 2026Updated: August 25, 2026

The HLA-A*31:01 genotype is a genetic marker used to predict adverse reactions to specific medications, particularly carbamazepine-induced hypersensitivity reactions.

Quick summary

HLA-A*31:01 genotype predicts risk of adverse drug reactions, notably to carbamazepine.

Medically reviewed by WellAlly Editorial TeamLast reviewed August 25, 2026Editorial policy

Key facts at a glance

Units
genotype
Clinical utility
predictive
Result kind
qualitative
FDA-cleared
Roche HLA-A*31:01, Thermo Fisher HLA-A*31:01
interpretation: {"text":"Presence of HLA-A*31:01 indicates an increased risk of hypersensitivity reactions to specific drugs, such as carbamazepine.","label":"Positive"}; {"text":"Absence of HLA-A*31:01 suggests a lower risk of drug-induced hypersensitivity reactions.","label":"Negative"}

The HLA-A*31:01 allele is a genetic variant of the human leukocyte antigen (HLA) system, which plays a crucial role in immune function. This allele is associated with an increased risk of hypersensitivity reactions to certain drugs.

Testing for HLA-A*31:01 is particularly relevant in the context of pharmacogenomics, as it can help identify patients who are at higher risk of developing severe adverse reactions to medications like carbamazepine, an anticonvulsant drug.

By identifying carriers of the HLA-A*31:01 allele, clinicians can make more informed decisions about drug selection and dosage, thereby improving patient safety and treatment outcomes.

Frequently asked questions

What is the clinical significance of HLA-A*31:01?
HLA-A*31:01 is clinically significant because it can predict an individual's risk of experiencing severe adverse reactions to certain medications, particularly carbamazepine.
How is the HLA-A*31:01 test performed?
The HLA-A*31:01 test is performed using genetic sequencing or PCR-based methods on a blood or saliva sample.
  1. 1
    HLA-A*31:01 and Carbamazepine-Induced Hypersensitivity ReactionsSource
  2. 2
    Pharmacogenomics of HLA-associated Drug HypersensitivitySource

Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.

This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.

Medical Disclaimer

This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.

If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.

Medically reviewed by WellAlly Editorial Team Last reviewed August 25, 2026. · Read our editorial policy