{{Rsnum
|rsid=56161402
|Gene=TPMT
|Chromosome=6
|position=18130762
|Orientation=plus
|GMAF=0.003673
|Assembly=GRCh38
|GenomeBuild=38.1
|dbSNPBuild=141
|Summary=known as R215H, encoding the TPMT*8 allele
|geno1=(C;C)
|geno2=(C;T)
|geno3=(T;T)
|Gene_s=TPMT
}}[[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 [http://www.ncbi.nlm.nih.gov/entrez/dispomim.cgi?id=187680&a=187680_AllelicVariant0006 (OMIM)]. This SNP was first identified in African-Americans.{{PMID|9931346}}

[[http://en.wikipedia.org/wiki/Thiopurine_methyltransferase| wikipedia]] thiopurine drugs metabolized by TPMT include [[azathioprine]], [[mercaptopurine]], and [[thioguanine]]
{{omim
|id=187680
|rsnum=56161402
|variant=0006
}}{{ClinVar
|rsid=56161402
|Reversed=0
|FwdREF=C
|FwdALT=T
|REF=C
|ALT=T
|RSPOS=18130993
|CHROM=6
|GMAF=0.0037
|dbSNPBuildID=129
|SSR=1
|SAO=1
|VP=0x050360000000040416110100
|GENEINFO=TPMT:7172
|GENE_NAME=TPMT
|GENE_ID=7172
|WGT=0
|VC=SNV
|CLNALLE=1
|CLNHGVS=NC_000006.11:g.18130993C>T
|CLNSRC=OMIM Allelic Variant
|CLNORIGIN=1
|CLNSRCID=187680.0006
|CLNSIG=5
|CLNCUI=C0342801
|CLNDBN=Thiopurine methyltransferase deficiency
|Disease=Thiopurine methyltransferase deficiency
|CLNACC=RCV000013563.21
|Tags=PM;S3D;SLO;VLD;HD;KGPhase1;KGPROD;OTHERKG;LSD;OM
|CAF=0.9963; 0.003673
|CLNDSDB=MedGen:OMIM:SNOMED_CT
|CLNDSDBID=C0342801:610460:238012003
|COMMON=1
}}{{GET Evidence
|gene=TPMT
|aa_change=Arg215His
|aa_change_short=R215H
|impact=pathogenic
|qualified_impact=Insufficiently evaluated pathogenic
|inheritance=unknown
|quality_scores=Array
|dbsnp_id=rs56161402
|overall_frequency_n=96
|overall_frequency_d=10756
|overall_frequency=0.00892525
|n_genomes=2
|n_genomes_annotated=0
|n_haplomes=2
|n_articles=0
|n_articles_annotated=0
|in_omim=Y
|nblosum100=1
|autoscore=3
|webscore=N
|n_web_uneval=8
}}