{{Rsnum
|rsid=3813929
|Gene=HTR2C
|Chromosome=X
|position=114584047
|Orientation=plus
|GMAF=0.1167
|Assembly=GRCh38
|GenomeBuild=38.1
|dbSNPBuild=141
|geno1=(C;C)
|geno2=(C;T)
|geno3=(T;T)
|Gene_s=HTR2C
}}{{ population diversity
| geno1=(C;C)
| geno2=(C;T)
| geno3=(T;T)
| CEU | 0.0 | 0.0 | 0.0
| HCB | 82.2 | 6.7 | 11.1
| JPT | 86.0 | 9.3 | 4.7
| YRI | 100.0 | 0.0 | 0.0
| ASW | 96.4 | 1.8 | 1.8
| CHB | 82.2 | 6.7 | 11.1
| CHD | 0.0 | 0.0 | 0.0
| GIH | 0.0 | 0.0 | 0.0
| LWK | 93.6 | 2.7 | 3.6
| MEX | 0.0 | 0.0 | 0.0
| MKK | 91.4 | 4.6 | 3.9
| TSI | 82.0 | 10.0 | 8.0
| HapMapRevision=28
}}[[rs3813929]], also known as -759C/T, is a SNP in the 5-hydroxytryptamine (serotonin) receptor 2C [[HTR2C]] gene.

A study of 107 patients with [[schizophrenia]] being treated with [[olanzapine]] reported a protective effect against weight-gain from the (T) allele of this SNP; zero patients (of 28) with a [[rs3813929]](T) allele had a body mass index increase of >=10% (p=0.002), whereas (C;C) homozygotes did. This effect may also involve nearby SNP [[rs518147]].{{PMID|19434072}}

{{PMID|20065966}} T allele showed borderline significant association with higher BMI and incidence of lifetime [[depression | major depressive disorder]] among 4978 persons from the European Prospective Investigation into Cancer (EPIC)-Norfolk study, however, only the association with BMI remained borderline significant within the full EPIC-Norfolk cohort (20,981 persons)
{{PMID Auto
|PMID=19416518
|Title=Investigation of the serotonin 2C receptor gene in attention deficit hyperactivity disorder in UK samples
|OA=1
}}

{{PharmGKB
|RSID=rs3813929
|Name_s=HTR2C: -759C/T; HTR2C:(-759)C>T
|Gene_s=HTR2C
|Feature=
|Evidence=PubMed ID:19636338
|Annotation=Risk or phenotype-associated allele: T. Phenotype: Short-term weight gain under olanzapine therapy was significantly lower for 5-HTR2C -759 T-allele carriers. Study size: 124. Study population/ethnicity: Caucasian; Patients with psychiatric disorders. Significance metric(s): p = 0.011. Type of association: PK.
|Drugs=olanzapine
|Drug Classes=
|Diseases=Weight gain
|Curation Level=Curated
|PharmGKB Accession ID=PA165109600
}}

{{PMID Auto
|PMID=19690620
|Title=Polymorphisms of serotonin receptor 2A and 2C genes and COMT in relation to obesity and type 2 diabetes
|OA=1
}}
{{PMID Auto
|PMID=20092861
|Title=Further exploration of the possible influence of polymorphisms in HTR2C and 5HTT on body weight
}}

{{PMID Auto
|PMID=20562674
|Title=Association between LEP and LEPR gene polymorphisms and dyslipidemia in patients using atypical antipsychotic medication
}}
{{PMID Auto
|PMID=20680028
|Title=Association between HTR2C gene polymorphisms and the metabolic syndrome in patients using antipsychotics: a replication study
}}
{{PMID Auto
|PMID=20504252
|Title=Association of HTR2C, but not LEP or INSIG2, genes with antipsychotic-induced weight gain in a German sample
}}

{{PharmGKB
|RSID=rs3813929
|Name_s=HTR2C:-759C/T; HTR2C:-759C>T
|Gene_s=HTR2C
|Feature=
|Evidence=PubMed ID:15666332
|Annotation=Risk or phenotype-associated allele: T. Phenotype: The T allele was more frequently found in subjects not gaining 10% or more of their body weight, compared with those who did gain 10% or more of their body weight. None of the subjects who gained >10% of their initial body weight over 6 weeks carried a T allele (0/11). Study size: 42. Study population/ethnicity: Caucasian acutely ill patients with schizophrenia taking olanzapine. Significance metric(s): p = 0.0035. Type of association: CO.
|Drugs=olanzapine
|Drug Classes=
|Diseases=Schizophrenia
|Curation Level=Curated
|PharmGKB Accession ID=PA165108056
}}

{{PharmGKB
|RSID=rs3813929
|Name_s=HTR2C: -759C/T
|Gene_s=HTR2C
|Feature=
|Evidence=PubMed ID:19622037
|Annotation=This variant is associated with Olanzapine-induced weight gain. The -759T allele confers protective effect towards Olanzapine-induced weight gain in a study consisting of 107 patients with schizophrenia.
|Drugs=olanzapine
|Drug Classes=
|Diseases=Schizophrenia; Weight gain
|Curation Level=Curated
|PharmGKB Accession ID=PA164924604
}}

{{PMID Auto
|PMID=21510767
|Title=Polymorphisms of the LEP-, LEPR and HTR2C gene: obesity and BMI change in patients using antipsychotic medication in a naturalistic setting
}}

{{PMID|17016522}} The association between HTR2C polymorphisms and obesity in psychiatric patients using antipsychotics: a cross-sectional study.

{{PMID|17291373}} Association of the HTR2C gene and antipsychotic induced weight gain: a meta-analysis.

{{PMID|17632216}} The association between HTR2C gene polymorphisms and the metabolic syndrome in patients with schizophrenia.

{{PMID|18081710|OA=1
}} Multivariate permutation analysis associates multiple polymorphisms with subphenotypes of major depression.

{{PMID|18802918}} Focus on HTR2C: A possible suggestion for genetic studies of complex disorders.

{{PMID|19142101}} HTR2C gene polymorphisms and the metabolic syndrome in patients with schizophrenia: a replication study.

{{PMID|19359258|OA=1
}} Cohort profile: risk patterns and processes for psychopathology emerging during adolescence: the ROOTS project.

{{PMID|20060656}} Association of polymorphisms of the serotonergic system with smoking initiation in Caucasians.

{{PMID|21162693|OA=1
}} Pharmacogenetics and antipsychotics: therapeutic efficacy and side effects prediction.

{{PMID|21391883}} Functional consequences of two HTR2C polymorphisms associated with antipsychotic-induced weight gain.

{{GET Evidence
|impact=pharmacogenetic
|qualified_impact=Insufficiently evaluated pharmacogenetic
|inheritance=unknown
|quality_scores=Array
|dbsnp_id=rs3813929
|overall_frequency_n=9
|overall_frequency_d=92
|overall_frequency=0.0978261
|n_genomes=8
|n_genomes_annotated=0
|n_haplomes=12
|n_articles=3
|n_articles_annotated=1
|in_pharmgkb=Y
|autoscore=1
|webscore=N
}}

{{PMID Auto
|PMID=23499153
|Title=Genetic polymorphisms of serotonin transporter and receptor 1A could influence success during embryo implantation and maintenance of pregnancy
}}

{{PMID Auto
|PMID=22914617
|Title=Analysis of the BTBD9 and HTR2C variants in Chinese Han patients with Tourette syndrome.
}}

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