Pharmacogenomics Flashcards
What is pharmacogenomics?
Pharmacogenomics is the study of the genetic basis for individual differences in drug responses, encompassing variability in drug efficacy and toxicity.
What factors contribute to variability in drug responses?
Variability arises from pharmacokinetic factors (absorption, distribution, metabolism, excretion) and pharmacodynamic factors (differences in drug target expression or function).
What are single nucleotide polymorphisms (SNPs)?
SNPs are the most common type of genetic variation, involving changes in a single nucleotide in the DNA sequence. Their effects depend on their position within the gene.
How do germline and somatic mutations differ?
Germline mutations are hereditary and present in every cell, while somatic mutations are acquired, occur in tumor cells, and are not heritable.
What is the role of TPMT in 6-mercaptopurine metabolism?
Thiopurine S-methyltransferase (TPMT) metabolizes 6-mercaptopurine. Genetic polymorphisms in TPMT result in varying activity levels, affecting drug toxicity and efficacy.
What are the TPMT activity phenotypes?
TPMT phenotypes include normal activity (H/H), intermediate activity (L/H), and low or no activity (L/L). L/L individuals are at high risk of severe toxicity.
What is the BRCA mutation and its significance?
BRCA1 and BRCA2 are tumor suppressor genes involved in DNA repair. Mutations in these genes increase the risk of breast and ovarian cancer.
How do PARP inhibitors work in BRCA-deficient cells?
PARP inhibitors, like olaparib, block DNA repair pathways, causing synthetic lethality in BRCA-mutated cancer cells.
What is the BRAF mutation and its relevance?
The BRAF V600E mutation leads to uncontrolled cell growth in cancers like metastatic melanoma. Vemurafenib targets tumors with this specific mutation.
What is the role of EGFR mutations in NSCLC treatment?
EGFR mutations predict responsiveness to EGFR tyrosine kinase inhibitors like gefitinib, used for non-small cell lung cancer (NSCLC) with activating mutations.
What is personalized medicine?
Personalized medicine tailors treatment based on an individual’s genetic profile, improving drug efficacy and minimizing toxicity.
How is pharmacogenomics used in oncology?
It is used to identify genetic polymorphisms that affect drug toxicity, develop targeted treatments, and improve survival rates for chemotherapeutics.
Why is studying genetic variability important?
Understanding genetic variability helps predict drug responses, design effective treatments, and reduce adverse effects.
