Table 5.

The CPIC Assignment of Likely HLA-B Phenotype Based on Genotype (2020)

HLA phenotypeGenotypeExamples of diplotypes
HLA-B*15:02 negativeHomozygous for any allele(s) other than HLA-B*15:02 *X/*X a
HLA-B*15:02 positiveHomozygous or heterozygous variant *15:02/*X a , *15:02/*15:02
a

Where *X = any HLA-B allele other than *15:02.

Table is adapted from (2).

Note: The nomenclature used in this table reflect the standardized pharmacogenetic terms proposed by CPIC (4).

From: Phenytoin Therapy and HLA-B*15:02 and CYP2C9 Genotype

Cover of Medical Genetics Summaries
Medical Genetics Summaries [Internet].
Pratt VM, Scott SA, Pirmohamed M, et al., editors.
Copyright Notice

All Medical Genetics Summaries content, except where otherwise noted, is licensed under a Creative Commons Attribution 4.0 International (CC BY 4.0) license which permits copying, distribution, and adaptation of the work, provided the original work is properly cited and any changes from the original work are properly indicated. Any altered, transformed, or adapted form of the work may only be distributed under the same or similar license to this one.

NCBI Bookshelf. A service of the National Library of Medicine, National Institutes of Health.