rs1128503 is a SNP in the transporter P-glycoprotein (P-gp) 170, encoded by the ABCB1 (also known as MDR1) gene. Methadone is a substrate of this protein, so variants may affect the efficacy and optimal dosage of this drug as used for treating opiate dependence.
A study of 98 methadone-maintaining patients concluded that the higher (>150 mg/day) and lower (< or =150 mg/day) methadone dose groups differed significantly in their rs1128503 status (experiment-wise p = 0.0325). Furthermore, individuals with the 3-locus genotype pattern (T;T)-(T;T)-(T;T) for SNPs rs1045642, rs2032582 and rs1128503, respectively, had an approximately 5-fold chance of requiring the 'higher' methadone dose, while individuals heterozygous for these three SNPs have an approximately 3-fold chance of stabilizing at the 'lower' methadone dose (point-wise p-value = 0.026).[PMID 18424454]
[PMID 19107781] Associations between ABCB1/MDR1 gene polymorphisms and Crohn's disease: a gene-wide study in a pediatric population
[PMID 19437139] ABCB1 single nucleotide polymorphisms in the Brazilian population
[PMID 21790905] CYP2B6 SNPs are associated with methadone dose required for effective treatment of opioid addiction
[PMID 22015057] Single nucleotide polymorphism associations with response and toxic effects in patients with advanced renal-cell carcinoma treated with first-line sunitinib: a multicentre, observational, prospective study
[PMID 22110582] Association of MDR1 Gene SNPs and Haplotypes with the Tacrolimus Dose Requirements in Han Chinese Liver Transplant Recipients
[PMID 21705081] Multidrug resistance gene expression and ABCB1 SNPs in plasma cell myeloma
[PMID 21806386] Pharmacogenetics of calcineurin inhibitors in Brazilian renal transplant patients
[PMID 22358301] ABCB1 genetic variation and P-glycoprotein expression/activity in a cohort of Brazilian acute myeloid leukemia patients
[PMID 22416375] [Genetic performance criteria valproate in patients with epilepsy]
[PMID 15197162] Identifying candidate causal variants responsible for altered activity of the ABCB1 multidrug resistance gene.
[PMID 16999857] ABCB1 genotypes and haplotypes in patients with dementia and age-matched non-demented control patients.
[PMID 17548681] MDR1 gene variants, indoor insecticide exposure, and the risk of childhood acute lymphoblastic leukemia.
[PMID 17913323] ABCB1 (MDR1) gene polymorphisms are associated with the clinical response to paroxetine in patients with major depressive disorder.
[PMID 18213362] Multiplexed genotyping of ABC transporter polymorphisms with the Bioplex suspension array.
[PMID 18547414] Genotyping panel for assessing response to cancer chemotherapy.
[PMID 18698231] Polymorphisms affecting gene transcription and mRNA processing in pharmacogenetic candidate genes: detection through allelic expression imbalance in human target tissues.
[PMID 18725235] Bidirectional translational research: Progress in understanding addictive diseases.
[PMID 18812236] No association of ABCB1 polymorphisms with drug-refractory epilepsy in a north Indian population.
[PMID 19155191] Opiate and cocaine addiction: from bench to clinic and back to the bench.
[PMID 19285141] Genetic determinants of target and novelty-related event-related potentials in the auditory oddball response.
[PMID 19694740] No significant effect of ABCB1 haplotypes on the pharmacokinetics of fluvastatin, pravastatin, lovastatin, and rosuvastatin.
[PMID 19740399] Influence of ABCB1 polymorphisms and haplotypes on tacrolimus nephrotoxicity and dosage requirements in children with liver transplant.
[PMID 19844206] Sequence variations of ABCB1, SLC6A2, SLC6A3, SLC6A4, CREB1, CRHR1 and NTRK2: association with major depression and antidepressant response in Mexican-Americans.
[PMID 20170205] Effect of CYP3A and ABCB1 single nucleotide polymorphisms on the pharmacokinetics and pharmacodynamics of calcineurin inhibitors: Part I.
[PMID 20214406] Effect of CYP3A and ABCB1 single nucleotide polymorphisms on the pharmacokinetics and pharmacodynamics of calcineurin inhibitors: Part II.
[PMID 20354687] Explaining variability in ciclosporin exposure in adult kidney transplant recipients.
[PMID 20389299] Pazopanib-induced hyperbilirubinemia is associated with Gilbert's syndrome UGT1A1 polymorphism.
[PMID 20533057] ABCB1/MDR1 gene polymorphisms as a prognostic factor in colorectal cancer.
[PMID 21102498] Cytochrome P450 genetic polymorphisms influence the serum concentration of calcineurin inhibitors in allogeneic hematopoietic SCT recipients.
[PMID 21172166] Pharmacogenetics of antidepressant response.
[PMID 21553324] Polymorphisms of the MDR1 and MIF genes in children with nephrotic syndrome.
[PMID 21840870] Association of ABCB1, 5-HT3B receptor and CYP2D6 genetic polymorphisms with ondansetron and metoclopramide antiemetic response in Indonesian cancer patients treated with highly emetogenic chemotherapy.
[PMID 21896346] Polymorphisms in genes that regulate cyclosporine metabolism affect cyclosporine blood levels and clinical outcomes in patients who receive allogeneic hematopoietic stem cell transplantation.
[PMID 22134106] ABCB1 haplotype is associated with major molecular response in chronic myeloid leukemia patients treated with standard-dose of imatinib.
[PMID 22136368] Influence of genomic ancestry on the distribution of SLCO1B1, SLCO1B3 and ABCB1 gene polymorphisms among Brazilians.
[PMID 22306099] Association between the functional polymorphism (C3435T) of the gene encoding P-glycoprotein (ABCB1) and major depressive disorder in the Japanese population.
[PMID 22569204] PharmGKB summary: phenytoin pathway.
|qualified_impact||Insufficiently evaluated pharmacogenetic|
[PMID 23188198] ABCB1 polymorphism predicts escitalopram dose needed for remission in major depression
[PMID 23546964] Frequency of MDR1 single nucleotide polymorphisms in a Jordanian population, including a novel variant
[PMID 23093106] Detection of frequent ABCB1 polymorphisms by high-resolution melting curve analysis and their effect on breast carcinoma prognosis
[PMID 23786015] [Pharmacogenetic criteria drug-resistence epilepsy]
[PMID 23917080] ABCB1 (MDR1) polymorphisms and ovarian cancer progression and survival: a comprehensive analysis from the Ovarian Cancer Association Consortium and The Cancer Genome Atlas