Sign in →

Test Code HTR2O Serotonin Receptor Genotype (HTR2A and HTR2C), Saliva

Reporting Name

Serotonin Receptor 2A/2C, Saliva

Useful For

Guiding treatment choice of a (selective serotonin reuptake inhibitor) SSRI or non-SSRI antidepressant


Guiding treatment choice in individuals who have a drug-metabolizer phenotype discordant with CYP450 genotypes


Identifying patients who may benefit from treatment with the antipsychotic drug clozapine and aripiprazole


Identifying those patients at risk of excessive weight gain when receiving antipsychotic medications


Genotyping patients who prefer not to have venipuncture done

Performing Laboratory

Mayo Medical Laboratories in Rochester

Specimen Type


Specimen Required

Multiple saliva genotype tests can be performed on a single specimen after a single extraction. See Multiple Saliva Genotype Tests in Special Instructions for a list of tests that can be ordered together.


Supplies: DNA Saliva Collection Kit (T651)

Container/Tube: Oragene DNA Self-Collection Kit (T651: fees apply)

Specimen Volume: Full tube

Collection Instructions:

1. Fill tube to line.

2. Send specimen in original container per kit instructions.

Specimen Minimum Volume

1 mL

Specimen Stability Information

Specimen Type Temperature Time
Saliva Ambient

Reference Values

An interpretive report will be provided.

Day(s) and Time(s) Performed

Wednesday; 8 a.m.

Test Classification

This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. This test has not been cleared or approved by the U.S. Food and Drug Administration.

CPT Code Information

81479-Unlisted molecular pathology procedure

LOINC Code Information

Result ID Test Result Name Result LOINC Value
32936 HTR2A -1438G>A 75726-0
32937 HTR2A 74C>A 75728-6
32938 HTR2A 102 T>C 75731-0
32939 HTR2A IVS2 A>G 75727-8
32940 HTR2A 1354 C>T 75729-4
32941 HTR2C -759 C>T 75732-8
32942 HTR2C 796 G>C 75730-2
32943 Reviewed By No LOINC Needed
32944 HTR2 Genotype 69047-9

Method Name

Polymerase Chain Reaction (PCR) with Allele-Specific Primer Extension (ASPE)


New York Clients-Informed consent is required. Please document on the request form or electronic order that a copy is on file. An Informed Consent for Genetic Testing (Supply T576) is available in Special Instructions.