From SNPedia
| Genotype | Effect |
| rs2235015(G;G) | 7x more likely to respond to certain antidepressants |
| rs2235015(G;T) | 7x more likely to respond to certain antidepressants |
| rs2235015(T;T) | 7x less likely to respond to certain antidepressants |
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
2 >= 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
2 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.10.1016/j.neuron.2007.11.017
The 9 SNPs in the linkage block identified are 10.1016/j.neuron.2007.11.017:
| ? | (G;G) (G;T) (T;T) |
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