Pharmacogenomics Key Concepts

A set of 25 vocabulary flashcards reviewing pharmacogenomics terminology, genetic variations, enzyme activity, and clinical gene-drug relationships.

Pharmacogenomics

The study of how genetic variations affect drug response, including drug efficacy, toxicity, and dosing decisions.

Genotype

A person's genetic makeup or allele combination, such as CYP2D6 1/4.

Phenotype

The observable effect of the genotype, such as metabolizer status or drug response.

Single Nucleotide Polymorphism (SNP)

A change in a single DNA base occurring in more than 1% of the population.

Mutation

A DNA change occurring in less than 1% of the population.

Major Allele

The most common allele in a population, occurring at a frequency greater than 50%.

Minor Allele

The less common allele in a population, occurring at a frequency less than 50%.

Haplotype

A group of single nucleotide polymorphisms (SNPs) inherited together.

Copy Number Variant (CNV)

A variation in the number of copies of a gene, where individuals may have fewer or more than two copies.

Coding SNP (cSNP)

A single nucleotide polymorphism that occurs within a protein-coding region and may alter protein function.

Regulatory SNP (rSNP)

A single nucleotide polymorphism that occurs in promoters or enhancers and affects transcription.

Structural RNA SNP (srSNP)

A single nucleotide polymorphism that affects RNA processing, splicing, stability, or transport.

Synonymous SNP

A coding region SNP where the DNA sequence changes but the amino acid stays the same, usually resulting in no protein change.

Missense SNP

A coding region SNP where a DNA change causes a different amino acid, which may change protein function.

Nonsense SNP

A coding region SNP where a DNA change creates a stop codon, resulting in a shortened protein and often loss of function.

Stop Codons

Specific DNA sequences that terminate protein translation, including TAA, TAG, and TGA.

TPMT*3A Variant

A gene variant that results in very low TPMT activity, reduced thiopurine metabolism, drug accumulation, and increased risk of life-threatening myelosuppression.

UGT1A1*28

A promoter variant containing (TA)7 repeats that leads to reduced enzyme expression, increased bilirubin, Gilbert syndrome, and increased irinotecan toxicity risk.

Microsatellite

Tandem DNA repeats consisting of 1 to 6 base pairs.

Minisatellite

Larger repeated sequences of tandem DNA compared to microsatellites.

Huntington Disease

A tandem repeat disease caused by a CAG repeat expansion.

CYP2D6*5

A CYP2D6 gene deletion variant that results in no enzyme function.

CYP2D6*1x3

A CYP2D6 gene duplication variant resulting in three copies of the gene, leading to more enzyme and faster metabolism.

Phenoconversion

A drug-induced change in metabolizer status where a patient's observable phenotype differs from their genotype.

CYP2D6 Inhibitors

Specific drugs including fluoxetine, paroxetine, and bupropion that inhibit CYP2D6 enzyme activity.