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rs1135840 CYP2D6

CYP2D6 4180G>C (S486T) reference. Shared variant in *2 and many other haplotypes.

Curated · human-reviewed Drug response · Risk / effect allele: G · dbSNP

What is rs1135840?

rs1135840 is a single-nucleotide polymorphism (SNP) in the CYP2D6 gene (Cytochrome P450 2D6). Each person carries two copies, one from each parent, so a result is reported as a pair of letters such as GG. The table below describes what studies associate with each genotype; the association is statistical, across populations, and is not a diagnosis.

What does each rs1135840 genotype mean?

GenotypeAssociationWhat the evidence saysConfidence
GGtypicalCYP2D6 4180G>C (S486T) reference. Shared variant in *2 and many other haplotypes.70%
GC / CGtypicalCYP2D6 4180G>C heterozygous.65%
CCtypicalCYP2D6 4180 variant homozygous.70%

How common is the G allele of rs1135840?

Minor-allele frequency by population (gnomAD / 1000 Genomes):

European40.0%
East Asian25.0%
African55.0%
South Asian35.0%
Admixed American35.0%
Global35.0%

Is rs1135840 on 23andMe and AncestryDNA chips?

Chip coverage is not recorded for this variant. Orviva reports it when a raw-data file contains it directly or via a well-correlated proxy SNP, and says so when it does not.

Sources

Genetic associations describe risk across populations, not a diagnosis for any one person. Most variants shift risk modestly and act alongside lifestyle, environment and other genes. Consumer DNA chips do not read every position and can be wrong at any single one. For general education only; talk to a clinician or genetic counsellor before acting on anything here, and never change a prescribed medicine without your prescriber.