Table 4.

CPIC (2014) Assignment of likely HLA-B Phenotypes based on Genotype

Likely phenotypeGenotypeExamples of diplotype
Very low risk of hypersensitivity (constitutes ~94%a of patients)Absence of *57:01 alleles (reported as “negative” on a genotyping test)*X/*Xb
High risk of hypersensitivity (~6% of patients)Presence of at least one *57:01 allele (reported as “positive” on a genotyping test)*57:01/*Xb
*57:01/*57:01

HLA-B, human leukocyte antigen B.

a

See supplementary data online for estimates of genotype frequencies among different ethnic/geographic groups.

b

*X = any HLA-B genotype other than *57:01.

Table adapted from (3).

From: Abacavir Therapy and HLA-B*57:01 Genotype

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Pratt VM, Scott SA, Pirmohamed M, et al., editors.
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