SULT1A1

SULT1A1 and topical minoxidil

Sulfotransferase 1A1

1 medication 1 brand product

About SULT1A1

SULT1A1 converts topical minoxidil into its active form, minoxidil sulfate. The SULT1A1*2 allele carries the functionally characterized rs1042028 variant, which has demonstrated reduced enzyme activity and stability in laboratory studies. This reduced function may limit minoxidil activation and contribute to a weaker treatment response.^[1]^[2]^[3]^[4]

Gene2Rx reports *1/*1 as Normal Function and both *1/*2 and *2/*2 as Decreased Function. The diplotype shows how many copies of *2 were identified. Full Reports include this targeted assessment for consumer DNA tests and whole-genome sequencing when the data supports a confident call; uncertain calls remain indeterminate. This interpretation concerns topical minoxidil.

What we test for SULT1A1

Gene2Rx uses definitions covering 2 named SULT1A1 star alleles, built from 1 variant in Gene2Rx definitions. Array and WGS; requires a supported direct or imputed rs1042028 result. Some uploads remain indeterminate. Topical minoxidil.

Star alleles

Defined variants

Gene2Rx definitions

Source

GRCh38

Genome build

Normal Function 1 Decreased Function 1

Supported SULT1A1 definitions

SULT1A1*2 carries the functionally characterized p.Arg213His variant at rs1042028. It has reduced enzyme activity and stability, which is relevant because SULT1A1 helps activate topical minoxidil. Read the functional evidence.

*1: Normal Function
*2: Decreased Function

What are star alleles?

Gene2Rx reports the targeted rs1042028 result using the established SULT1A1*1 and *2 names. *1 identifies the reference allele at this position; *2 identifies the decreased-function p.Arg213His variant. Your pair of alleles is shown as *1/*1, *1/*2, or *2/*2 when the call is confident.

This targeted screen does not resolve other SULT1A1 alleles or gene copy-number changes. The reported phenotype describes the predicted function associated with this result; it is not a direct measurement of enzyme activity in your hair follicles.

Medications with SULT1A1 information

This list contains 1 medication with SULT1A1 information from the sources shown below. Evidence and report eligibility differ by drug; each page explains its scope and limitations.

hair loss →

Topical minoxidil Gene2Rx

Brand products containing a SULT1A1-affected ingredient

These branded medications include at least one active ingredient whose metabolism or action involves SULT1A1. Each links to its full pharmacogenetic breakdown.

Rogaine

minoxidil

References

Raftogianis et al. Phenol sulfotransferase pharmacogenetics in humans: association of common SULT1A1 alleles with TS PST phenotype (1997). pubmed.ncbi.nlm.nih.gov
Li et al. Characterization of human liver SULT1A1 allozymes with triiodothyronine as the substrate (2001). pubmed.ncbi.nlm.nih.gov
Roberts et al. Sulfotransferase activity in plucked hair follicles predicts response to topical minoxidil in the treatment of female androgenetic alopecia (2014). pubmed.ncbi.nlm.nih.gov
Gaboardi et al. 26-SNP Panel Aids Guiding Androgenetic Alopecia Therapy and Provides Insight into Mechanisms of Action (2025). mdpi.com
Jimenez-Cauhe et al. Hair follicle sulfotransferase activity and effectiveness of oral minoxidil in androgenetic alopecia (2024). pubmed.ncbi.nlm.nih.gov

Explore SULT1A1 in your report

Your Full Report includes a SULT1A1 interpretation for topical minoxidil when your array or WGS data provides a confident direct or imputed variant call. Explore what your genetics may contribute to treatment response.

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Informational only, not medical advice. The presence of a SULT1A1 pharmacogenetic guideline does not mean every patient needs to change their dose. Never start, stop, or change a medication without talking to your prescribing clinician.