Updated Phenotype Terminology

YouScript and Genelex Labs have updated their phenotype names to be consistent with the standardized terms for clinical pharmacogenetic test results proposed by the Clinical Pharmacogenetics Implementation Consortium (CPIC) in the July 2016 issue of Genetics in Medicine. Like CPIC, we believe that implementing standardized terminology is an important step toward the widespread adoption of clinical pharmacogenetics. These standard terms will improve the understanding and interpretation of pharmacogenetic tests, reduce confusion by maintaining consistent nomenclature, and facilitate pharmacogenetic data sharing across diverse health care records systems with clinical decision support. You can find a summary of the updated YouScript/Genelex phenotype names in Table 1 below. Additionally, here is what you can expect to see in regards to these standardized phenotype terms moving forward:

  • For drug metabolizing enzymes: (Ex. CYP2C19, CYP2D6, CYP3A5, TPMT, DPYD, etc.)
    • Ultrarapid Metabolizer
    • Rapid Metabolizer
    • Normal Metabolizer
    • Intermediate Metabolizer
    • Poor Metabolizer
  • For drug transporters: (Ex. SLCO1B1, SLC6A4, etc.)
    • Normal Function
    • Decreased Function
    • Poor Function
  • For high-risk genotype status: (Ex. HLA-B, HLA-A, etc.)
    • Positive
    • Negative


Table 1: YouScript/Genelex Labs Major Phenotype Name Changes

Old Phenotype New Phenotype
CYP2C19 Ultra Rapid Metabolizer

(*1/*17 and *17/*17)

CYP2C19 Rapid Metabolizer (*1/*17)

CYP2C19 Ultrarapid Metabolizer (*17/*17)

CYP3A5 Expresser

CYP3A5 Intermediate Expresser

CYP3A5 Non-Expresser

CYP3A5 Normal Metabolizer

CYP3A5 Intermediate Metabolizer

CYP3A5 Poor Metabolizer

DPYD Normal Activity

DPYD Intermediate Activity

DPYD Deficient Activity

DPYD Normal Metabolizer

DPYD Intermediate Metabolizer

DPYD Poor Metabolizer

TPMT Normal Activity

TPMT Intermediate Activity

TPMT Deficient Activity

TPMT Normal Metabolizer

TPMT Intermediate Metabolizer

TPMT Poor Metabolizer

SLCO1B1 Normal Transporter

SLCO1B1 Intermediate Transporter

SLCO1B1 Poor Transporter

SLCO1B1 Normal Function

SLCO1B1 Decreased Function

SLCO1B1 Poor Function

SLC6A4 Normal Serotonin Transporter

SLC6A4 Intermediate Serotonin Transporter

SLC6A4 Poor Serotonin Transporter

SLC6A4 Normal Function

SLC6A4 Decreased Function

SLC6A4 Poor Function