{{Rsnum
|rsid=2235015
|Gene=ABCB1
|Chromosome=7
|position=87570248
|Orientation=plus
|GMAF=0.202
|Assembly=GRCh38
|GenomeBuild=38.1
|dbSNPBuild=141
|geno1=(G;G)
|geno2=(G;T)
|geno3=(T;T)
|Gene_s=ABCB1
}}{{ population diversity
| geno1=(G;G)
| geno2=(G;T)
| geno3=(T;T)
| CEU | 55.8 | 39.8 | 4.4
| HCB | 91.2 | 8.8 | 0.0
| JPT | 82.3 | 15.9 | 1.8
| YRI | 28.1 | 46.6 | 25.3
| ASW | 50.9 | 36.8 | 12.3
| CHB | 91.2 | 8.8 | 0.0
| CHD | 92.6 | 7.4 | 0.0
| GIH | 65.3 | 30.7 | 4.0
| LWK | 35.5 | 49.1 | 15.5
| MEX | 70.7 | 29.3 | 0.0
| MKK | 43.6 | 35.9 | 20.5
| TSI | 65.3 | 30.7 | 4.0
| HapMapRevision=28
}}[[rs2235015]] is a SNP in the [[ABCB1]] gene (also known as the MDR1 gene), which encodes a protein that transports certain molecules across the blood-brain barrier. SNPs in [[ABCB1]] may thus influence the intracerebral concentrations of certain drugs and thus their efficacy or potential for adverse side effects. [[rs2032583]] is near 9 SNPs found within a tight linkage block (r<sup>2</sup> >= 0.8 ) such that the minor allele at any one of them predicts (with ~80%+ accuracy) that the other SNPs will also be the minor allele. The list of the 9 SNPs is shown below. [[rs2235015]] has an r<sup>2</sup> value of >0.5 with this group.

When treated for [[depression]] with substrates of the protein encoded by [[ABCB1]], carriers of one or two minor alleles at these [[ABCB1]] SNPs have been reported to respond better than non-carriers. The [[antidepressant]] drugs that are known to be substrates include [[citalopram]], [[paroxetine]], [[amitriptyline]], and [[venlafaxine]]. The relative odds of better response for [[rs2235015]](T) carriers is 7.72 (CI: 2.8-21.3, p=0.000065) based on a study of ~400 primarily Caucasian patients.{{doi|10.1016/j.neuron.2007.11.017}}

The 9 SNPs in the linkage block identified are {{doi|10.1016/j.neuron.2007.11.017}}:
* [[rs2235067]]
* [[rs4148740]]
* [[rs2032583]]
* [[rs4148739]]
* [[rs11983225]]
* [[rs2235040]]
* [[rs12720067]]
* [[rs7787082]]
* [[rs10248420]]

{{PharmGKB
|RSID=rs2235015
|Name_s=
|Gene_s=ABCB1
|Feature=Intron
|Evidence=PubMed ID:18215618
|Annotation=This variant is associated with differences in clinical efficacy of antidepressants, most likely by influencing their access to the brain.
|Drugs=amitriptyline; citalopram; paroxetine; venlafaxine
|Drug Classes=
|Diseases=Depression
|Curation Level=Curated
|PharmGKB Accession ID=PA161615692
}}

{{PMID Auto
|PMID=18382661
|Title=Pharmacokinetic genes do not influence response or tolerance to citalopram in the STAR*D sample.
|OA=1
}}

{{PMID Auto
|PMID=18535201
|Title=A genome-wide scan for common genetic variants with a large influence on warfarin maintenance dose.
|OA=1
}}

{{PMID Auto
|PMID=21172166
|Title=Pharmacogenetics of antidepressant response.
|OA=1
}}

{{PMID Auto
|PMID=22641028
|Title=ABCB1 gene variants influence tolerance to selective serotonin reuptake inhibitors in a large sample of Dutch cases with major depressive disorder.
}}

{{GET Evidence
|impact=pharmacogenetic
|qualified_impact=Insufficiently evaluated pharmacogenetic
|inheritance=unknown
|quality_scores=Array
|dbsnp_id=rs2235015
|overall_frequency_n=2665
|overall_frequency_d=10756
|overall_frequency=0.247769
|n_genomes=22
|n_genomes_annotated=0
|n_haplomes=31
|n_articles=1
|n_articles_annotated=0
|in_pharmgkb=Y
|autoscore=1
|webscore=N
}}

{{PMID Auto
|PMID=22672924
|Title=Polymorphisms of the drug transporter gene ABCB1 predict side effects of treatment with cabergoline in patients with PRL adenomas
}}

{{on chip | 23andMe v1}}
{{on chip | 23andMe v2}}
{{on chip | 23andMe v3}}
{{on chip | 23andMe v4}}
{{on chip | FTDNA2}}
{{on chip | HumanOmni1Quad}}
{{on chip | Illumina Human 1M}}