rs56161402

A SNP in the TPMT gene on chromosome 6. Its most notable genotype is T;T: TPMT*8 homozygote; likely issues detoxifying certain drugs

Gene
TPMT
Location
Chr 618,130,762 (GRCh38)
Highest magnitude
2.5Worth knowing
Tested on
AncestryDNA
Minor allele frequency
<1%

Genotypes

As shown in 23andMe and AncestryDNA files.

  1. C;CGoodcommon in clinvarTypical · 0.0
  2. C;TNot ratedTPMT*8 heterozygote; possible issues detoxifying certain drugsMinor · 1.5
  3. T;TMost notableNot ratedTPMT*8 homozygote; likely issues detoxifying certain drugsWorth knowing · 2.5

On SNPedia: (C;C), (C;T), (T;T). Magnitude rates how notable a genotype is from 0 to 10, not how risky it is.

Conditions, medicines and genes

Other TPMT SNPs

All TPMT SNPs

Notes

From SNPedia

Notes

rs56161402, also known as R215H or Arg215His, is a relatively rare SNP in the TPMT gene. This SNP potentially encodes a variant incapable of detoxifying byproducts of certain antineoplastic and immunosuppressant drugs. In general, individuals must have two nonfunctioning TPMT alleles for the toxicity to be pronounced. The risk allele for this SNP (in orientation to the dbSNP entry) is rs56161402(T), and it encodes the TPMT*8 allele (OMIM). This SNP was first identified in African-Americans. wikipedia thiopurine drugs metabolized by TPMT include azathioprine, mercaptopurine, and thioguanine 23andMe name: i6019070

Source and license

Adapted from rs56161402 on SNPedia, using a snapshot taken October 16, 2026. SNPedia content is shared under CC BY-NC-SA 3.0 US, and this page is shared under the same license.

SNPedia is a community-edited wiki. Its entries can be incomplete, out of date or wrong, and nothing here is a diagnosis or medical advice. Magnitude is a community rating of how interesting a genotype is, not a risk score.