How to Read Your Gene2Rx Report

The top of every report has these four steps. On a phone they sit behind a "How to read this report" row that you tap to open.

1. Step 1

   Two copies of each gene

   You inherit one copy from each parent. The report names the pair, such as *1/*2.

2. Step 2

   The pair gives a gene result

   Such as Poor metabolizer. The color shows it: typical, reduced, poor.

3. Step 3

   The result sets each medication's label

   Consider alternative Use with caution Use as directed Unable to determine

4. Step 4

   Then talk to your prescriber

   Don't change or stop a medication on your own. Unable to determine doesn't mean normal.

The rest of this guide goes through each of those steps in more detail.

The report opens with its name, who it was made for, its version and the date it was made. Underneath are four facts about the data it used:

• Data source: where your DNA data came from, such as 23andMe, AncestryDNA or a whole-genome file. The example used 23andMe.
• Genome build: the version of the human reference genome your file uses, GRCh37 or GRCh38. You don't need to do anything with it; it helps if you ever compare reports.
• Genes analyzed: how many genes the report reads (30 in the example).
• Medications: how many medications your report covers (120 in the example).

The PDF button downloads a printable copy. There are two versions, described in The two PDFs below.

Below that is a bar with the report's sections: Summary, All medications, Genes and About. It stays at the top of the screen as you scroll, along with a search box. Type a medication's generic or brand name, a drug class or a gene, and the search box suggests matches as you type. The summary starts with a bigger version of the same search, "What are you looking for?", with shortcuts to the drug classes people look up most.

The first results in the summary are your most important genes: up to three that change guidance for the most medications. These are the example's top two:

CYP2D6

*4/*4

Poor metabolizer

Neither copy works. CYP2D6 turns on or clears about 1 in 4 prescription drugs. These include many drugs for depression, pain and ADHD.

Changes the guidance for 45 of your medications

CYP2C19

*1/*2

Intermediate metabolizer

One copy works and one doesn't. CYP2C19 handles several SSRIs, acid reducers such as omeprazole, and the blood thinner clopidogrel.

Changes the guidance for 17 of your medications

Each card has the same parts:

• The gene's name, top left, with two dots: one for each copy of the gene you inherited.
• The two copies' names, top right, such as *4/*4. This pair is called a diplotype.
• The result, in large type, such as Poor metabolizer. This is what the pair of copies means for how the gene works.
• A plain-language line on what the two copies do and what the gene does in your body.
• How many of your medications it changes. In the report, this link narrows the medication list to those medications.

Below the cards, "Also not typical" lists your other results that differ from the most common one, each linking to its gene. If none of your genes changes anything, the report says so in a single card instead.

Next comes Your genes at a glance, a compact table of every gene in the report with its dots, result and diplotype. Select any gene to jump to its full explanation.

Every gene in the report is shown the same way, whether it's in the summary or in the Genes section near the end. Here is the example's CYP2D6 result as it appears in the Genes section:

• CYP2D6

  Turns on or clears about 1 in 4 prescription drugs. These include many drugs for depression, pain and ADHD.

  Poor metabolizer*4/*4 · Neither copy works.
  0.0 activity scoreTypical: 1.25 to 2.25
  47 medicationsChanges the guidance for 45
  CYP2D6 poor metabolizer: estimated in 0.3% to 6.5% of people across population groups

  These CPIC estimates describe this phenotype, not your exact DNA combination or your chance of side effects. Frequencies vary by population; no ancestry is assumed for you.

  African American/Afro-Caribbean

  2.3%

  American

  2.0%

  Central/South Asian

  2.4%

  East Asian

  0.8%

  European

  6.5%

  Latino

  3.1%

  Near Eastern

  2.2%

  Oceanian

  0.3%

  Sub-Saharan African

  2.0%

  Estimated from published allele frequencies, rather than a direct count of people with this result. Study coverage and methods vary. Reference: CPIC CYP2D6 frequency table and methods. Data retrieved 2026-10-17.

Two copies, named with stars

You have two copies of each gene, one from each parent. Many drug-processing genes have standard names for their versions, called star alleles: *1, *2, *4 and so on. The report shows your two side by side, such as CYP2D6 *4/*4.

*1 is usually the most common, fully working version. The other numbers are just names, given in the order scientists described them. A bigger number isn't worse: *2 can work normally while *4 doesn't work at all. What matters is what each copy does, which the dots show.

The dots: what each copy does

Each dot is one copy. Its fill shows whether that copy works:

• works normally
• works less well
• doesn't work
• works faster than usual
• couldn't be checked

Here is how that plays out in four of the example's genes:

• CYP2C19

  Handles several SSRIs, acid reducers such as omeprazole, and the blood thinner clopidogrel.

  Intermediate metabolizer*1/*2 · One copy works and one doesn't.
  21 medicationsChanges the guidance for 17
  CYP2C19 intermediate metabolizer: estimated in 19.0% to 45.9% of people across population groups

  These CPIC estimates describe this phenotype, not your exact DNA combination or your chance of side effects. Frequencies vary by population; no ancestry is assumed for you.

  African American/Afro-Caribbean

  31.4%

  American

  21.4%

  Central/South Asian

  40.8%

  East Asian

  45.9%

  European

  26.1%

  Latino

  19.0%

  Near Eastern

  23.5%

  Oceanian

  36.9%

  Sub-Saharan African

  29.9%

  Estimated from published allele frequencies, rather than a direct count of people with this result. Study coverage and methods vary. Reference: CPIC CYP2C19 frequency table and methods. Data retrieved 2026-10-17.

• CYP2C9

  Clears warfarin, phenytoin, celecoxib and some other pain relievers.

  Intermediate metabolizer*1/*2 · One copy works and one works less well.
  1.5 activity scoreTypical: 2
  16 medicationsChanges the guidance for 8
  CYP2C9 intermediate metabolizer: estimated in 8.7% to 36.2% of people across population groups

  These CPIC estimates describe this phenotype, not your exact DNA combination or your chance of side effects. Frequencies vary by population; no ancestry is assumed for you.

  African American/Afro-Caribbean

  23.6%

  American

  16.4%

  Central/South Asian

  36.2%

  East Asian

  15.2%

  European

  34.5%

  Latino

  24.6%

  Near Eastern

  35.9%

  Oceanian

  8.7%

  Sub-Saharan African

  26.3%

  Estimated from published allele frequencies, rather than a direct count of people with this result. Study coverage and methods vary. Reference: CPIC CYP2C9 frequency table and methods. Data retrieved 2026-10-17.

• CYP1A2

  Breaks down caffeine and some medicines, such as clozapine.

  Rapid metabolizer*1/*30 · One copy works normally and one works faster than usual.
  1 medicationChanges the guidance for 1
• CYP3A4

  Breaks down more prescription drugs than any other enzyme.

  Normal metabolizer*1/*1 · Both copies work normally.
  1 medicationGuidance unchanged

• CYP2C19 *1/*2, intermediate metabolizer. One copy works and one doesn't. With half the usual working copies, the body handles CYP2C19's medications more slowly than most people.
• CYP2C9 *1/*2, intermediate metabolizer. One copy works and one works less well. The half-filled dot is a copy that works, just less well. The result has the same name as CYP2C19's, but for a different reason.
• CYP1A2 *1/*30, rapid metabolizer. One copy works normally and one works faster than usual. A copy that works faster than usual can clear a medication sooner, so it may wear off early.
• CYP3A4 *1/*1, normal metabolizer. Both copies work normally. Most people's results for most genes look like this. A typical result still appears in the report, and the medications it affects still get guidance, usually "Use as directed".

The color: the overall result

The dots' color sums up the gene's result, so you can scan a list for the ones that matter:

• Normal / typical / favorable
• Intermediate / decreased
• Poor / increased risk
• Rapid / increased
• Not determined

The words "metabolizer" and "function" describe how fast a gene processes drugs or how well it does its job. A poor metabolizer has little or no working enzyme, an intermediate metabolizer has less than usual, a normal metabolizer has the usual amount, and a rapid or ultrarapid metabolizer has more. None of these is a diagnosis. Each one only matters when you take a medication that depends on that gene.

Activity scores

A few genes, such as CYP2D6 and CYP2C9, also get an activity score. Each copy counts for a set amount (a working copy is usually 1, a weaker copy less, a copy that doesn't work 0) and the two are added up. The bar shows your score against the typical range. The example's CYP2D6 score is 0.0, against a typical range of 1.25 to 2.25. Guidelines use the score to decide which result, and so which recommendation, applies.

Genes named by DNA letters

Some genes don't have star alleles. For these, the report names the single DNA position that matters, such as rs4680, and your two letters at it. Where the letters have a known effect on how the gene works, they get dots like any other gene. Where they change a risk rather than a speed, they show as lettered dots.

• COMT

  Breaks down dopamine and other brain chemicals.

  Intermediate functionrs4680A/rs4680G · One copy works and one works less well.
  3 medicationsChanges the guidance for 1
  COMT rs4680 A allele: 27.4% to 66.4% of DNA copies across ancestry groups

  Your result has 1 copy of this allele. These gnomAD frequencies count DNA copies, not people who share your genotype or phenotype, and do not measure your chance of side effects. No ancestry is assumed for you.

  Counts below show copies of the A allele / total DNA copies measured.

  African / African American

  31.0%12,853 / 41,484

  Admixed American

  40.4%6,184 / 15,292

  Amish

  66.4%604 / 910

  Ashkenazi Jewish

  45.3%1,571 / 3,466

  East Asian

  27.4%1,414 / 5,152

  Finnish

  55.3%5,854 / 10,592

  Middle Eastern

  46.9%138 / 294

  European (non-Finnish)

  51.8%35,191 / 67,942

  South Asian

  44.5%2,147 / 4,822

  Remaining ancestry group

  41.8%883 / 2,110

  Reference: gnomAD v4.1 genomes, GRCh38 22-19963748-G-A. Frequencies are allele count divided by allele number within each ancestry group. Study groups are not representative of the worldwide population. Data retrieved 2026-10-17.

• CHRNA5

  A nicotine receptor in the brain linked to heavy smoking.

  AAIncreased riskrs16969968A/rs16969968A
  1 medicationChanges the guidance for 1
  CHRNA5 rs16969968 A allele: 3.2% to 40.7% of DNA copies across ancestry groups

  Your result has 2 copies of this allele. These gnomAD frequencies count DNA copies, not people who share your genotype or phenotype, and do not measure your chance of side effects. No ancestry is assumed for you.

  Counts below show copies of the A allele / total DNA copies measured.

  African / African American

  5.9%2,458 / 41,526

  Admixed American

  22.6%3,458 / 15,290

  Amish

  40.7%368 / 904

  Ashkenazi Jewish

  37.5%1,302 / 3,470

  East Asian

  3.2%166 / 5,186

  Finnish

  32.7%3,455 / 10,568

  Middle Eastern

  40.1%118 / 294

  European (non-Finnish)

  34.7%23,587 / 67,982

  South Asian

  22.2%1,069 / 4,826

  Remaining ancestry group

  27.5%581 / 2,112

  Reference: gnomAD v4.1 genomes, GRCh38 15-78590583-G-A. Frequencies are allele count divided by allele number within each ancestry group. Study groups are not representative of the worldwide population. Data retrieved 2026-10-17.

COMT rs4680A/rs4680G means one A and one G at position rs4680, which gives intermediate function. CHRNA5 rs16969968A/rs16969968A means two copies of the A letter at rs16969968, which is linked to an increased risk of heavy smoking. A "risk" result like this one says something about a tendency, not about how fast a drug is cleared.

Transporters and drug targets

Not every gene breaks drugs down. Some move drugs into cells, and some make the protein a drug acts on. Their results read slightly differently:

• SLCO1B1

  Moves statins into the liver.

  Decreased function*15/*1A · One copy works and one works less well.
  7 medicationsChanges the guidance for 6
  SLCO1B1 decreased function: estimated in 0% to 36.5% of people across population groups

  These CPIC estimates describe this phenotype, not your exact DNA combination or your chance of side effects. Frequencies vary by population; no ancestry is assumed for you.

  African American/Afro-Caribbean

  2.0%

  American

  36.5%

  Central/South Asian

  13.0%

  East Asian

  21.8%

  European

  28.3%

  Near Eastern

  32.0%

  Oceanian

  0%

  Sub-Saharan African

  5.4%

  Estimated from published allele frequencies, rather than a direct count of people with this result. Study coverage and methods vary. Reference: CPIC SLCO1B1 frequency table and methods. Data retrieved 2026-10-17.

• VKORC1

  Recycles vitamin K and is the protein warfarin blocks.

  AGDecreased expression-1639A/-1639G
  1 medicationChanges the guidance for 1
  VKORC1 rs9923231 -1639A allele: 10.0% to 89.2% of DNA copies across ancestry groups

  Your result has 1 copy of this allele. These gnomAD frequencies count DNA copies, not people who share your genotype or phenotype, and do not measure your chance of side effects. No ancestry is assumed for you.

  Counts below show copies of the -1639A allele / total DNA copies measured.

  African / African American

  10.0%4,141 / 41,504

  Admixed American

  39.1%5,974 / 15,262

  Amish

  44.2%400 / 906

  Ashkenazi Jewish

  49.9%1,734 / 3,472

  East Asian

  89.2%4,612 / 5,172

  Finnish

  39.1%4,127 / 10,558

  Middle Eastern

  53.4%156 / 292

  European (non-Finnish)

  37.8%25,693 / 67,986

  South Asian

  17.8%859 / 4,824

  Remaining ancestry group

  38.9%824 / 2,116

  Reference: gnomAD v4.1 genomes, GRCh38 16-31096368-C-T. Frequencies are allele count divided by allele number within each ancestry group. Study groups are not representative of the worldwide population. Data retrieved 2026-10-17.

SLCO1B1 carries statins into the liver, so decreased function means more statin stays in the blood, which raises the chance of muscle side effects. VKORC1 makes the protein that warfarin blocks, so decreased expression means less of it to block, and a smaller warfarin dose has the same effect.

Genes your data couldn't show

Sometimes a gene can't be read from your data, usually because a DNA chip doesn't test the positions that matter. The report draws these with dotted gray outlines and the words "Not checked". It never draws them as normal.

• RYR1

  A muscle channel. Rare changes in it can cause a dangerous reaction to some anesthetics.

  Not checkedWe couldn't check this gene from your data. This does not mean that a normal response is expected.
  7 medicationsShown as "Unable to determine"

The medications that depend on a gene like this get the label "Unable to determine", described below. For RYR1 and CACNA1S, the genes behind a rare, serious reaction to some anesthetics, the Full Report also adds a note to the summary:

Anesthesia genes couldn't be checked. RYR1 and CACNA1S can't be read reliably from array data, so 7 anesthesia medications show "Unable to determine." This is not a negative result. If you or a relative ever reacted badly to anesthesia, tell your anesthesia team.

How common is your result?

Many genes in the Genes section have a "How common is this result?" link. It opens the share of people with the same result in different populations, from published reference data. It's there for context only. A rare result isn't more serious, and a common one isn't safer.

CYP2D6 poor metabolizer: estimated in 0.3% to 6.5% of people across population groups

These CPIC estimates describe this phenotype, not your exact DNA combination or your chance of side effects. Frequencies vary by population; no ancestry is assumed for you.

African American/Afro-Caribbean

2.3%

American

2.0%

Central/South Asian

2.4%

East Asian

0.8%

European

6.5%

Latino

3.1%

Near Eastern

2.2%

Oceanian

0.3%

Sub-Saharan African

2.0%

Estimated from published allele frequencies, rather than a direct count of people with this result. Study coverage and methods vary. Reference: CPIC CYP2D6 frequency table and methods. Data retrieved 2026-10-17.

Every medication in the report gets one of four labels. The label says what the guidelines suggest for someone with your results, and the line beside it says why in plain language. Here is one medication with each label from the example:

VenlafaxineEffexor XR Consider alternative Your body breaks down this drug much more slowly, which has been linked to more side effects. A different antidepressant may be a better choice.CYP2D6Poor metabolizer

CYP2D6Poor metabolizer

CPIC guideline

Consider alternative Evidence: optionalRead the guideline (Clinical Pharmacogenetics Implementation Consortium, opens in a new tab)

In plain words

Your body breaks down this drug much more slowly, which has been linked to more side effects. A different antidepressant may be a better choice.

What it means

Decreased metabolism of venlafaxine to the active metabolite O-desmethylvenlafaxine and greatly decreased O-desmethylvenlafaxine:venlafaxine ratio compared with normal and intermediate metabolizers. Although the clinical impact is unclear, poor metabolizer status has been associated with adverse effects.

What the guideline suggests

Consider a clinically appropriate alternative antidepressant not predominantly metabolized by CYP2D6.

FDA drug label

Use with caution See the FDA table (U.S. Food and Drug Administration, opens in a new tab)

In plain words

Your body breaks down venlafaxine much more slowly than normal, causing the drug to build up in your system. A lower dose may be needed to avoid side effects.

What it means

Alters systemic parent drug and metabolite concentrations. Consider dosage reductions.

What the label suggests

Consider dosage reductions.

See full details for venlafaxine

CitalopramCelexa Use with caution Your body may break down the drug more slowly, increasing side effects. Your doctor may use a lower dose or adjust it more slowly.CYP2C19Intermediate metabolizer

CYP2C19Intermediate metabolizer

CPIC guideline

Use with caution Evidence: moderateRead the guideline (Clinical Pharmacogenetics Implementation Consortium, opens in a new tab)

In plain words

Your body may break down the drug more slowly, increasing side effects. Your doctor may use a lower dose or adjust it more slowly.

What it means

Reduced metabolism when compared with CYP2C19 normal metabolizers. Higher plasma concentrations may increase the probability of side effects.

What the guideline suggests

Initiate therapy with recommended starting dose. Consider a slower titration schedule and lower maintenance dose than normal metabolizers.

FDA drug label

Use as directed See the FDA table (U.S. Food and Drug Administration, opens in a new tab)

In plain words

Your body breaks down citalopram slightly slower than normal. The standard dose should work as expected.

What it means

No FDA guidance for your genotype

What the label suggests

Initiate therapy with recommended starting dose.

See full details for citalopram

QuetiapineSeroquel Use as directed Your CYP3A4 gene works normally, so the standard dose of this drug is used.CYP3A4Normal metabolizer

CYP3A4Normal metabolizer

DPWG guideline

Evidence: moderateRead the guideline (Dutch Pharmacogenetics Working Group, opens in a new tab)

In plain words

Your CYP3A4 gene works normally, so the standard dose of this drug is used.

What it means

No clinically significant effect on quetiapine metabolism.

What the guideline suggests

Use standard quetiapine dosing.

See full details for quetiapine

Desflurane Unable to determine We couldn't check the genes for this anesthesia reaction from your data. This does not mean that a normal response is expected.RYR1No resultCACNA1SNo result

RYR1No result+CACNA1SNo result

CPIC guideline, both genes together

Read the guideline (Clinical Pharmacogenetics Implementation Consortium, opens in a new tab)

In plain words

We couldn't check the genes for this anesthesia reaction from your data. This does not mean that a normal response is expected.

What it means

Malignant hyperthermia susceptibility could not be determined.

What the guideline suggests

Clinical findings, family history and clinical evaluation should guide anesthesia decisions.

CPIC reads your RYR1 and CACNA1S results together for desflurane, so this label reflects both genes.

See full details for desflurane

Consider alternative

A guideline suggests a different medication, because with your results this one may not work or is more likely to cause serious side effects. This is the label to raise with your prescriber first. It doesn't mean the medication is forbidden.

Use with caution

The medication can usually still be used, but a guideline suggests a change: a different dose, a slower start or closer monitoring.

Use as directed

Your results don't call for a change. Normal prescribing advice applies. It doesn't mean the medication is right for you, only that your genes don't argue against it.

Unable to determine

The report couldn't read a gene this medication depends on. This is not a normal result. If the medication matters to you, a clinical test can check that gene.

Under each medication's name are the genes behind its label, each with its dots and result. When a medication depends on several genes, the label follows the most cautious result.

Select any medication to open it. You'll see what the guidelines say and a "See full details" link to the medication's own page. Here is codeine, closed, and then the guideline cards it opens to:

CodeineTylenol 3 Consider alternative Your body turns very little codeine into its active form, so it likely won't ease your pain. A different pain reliever is usually suggested.CYP2D6Poor metabolizer

CYP2D6Poor metabolizer

CPIC guideline

Consider alternative Evidence: strongRead the guideline (Clinical Pharmacogenetics Implementation Consortium, opens in a new tab)

In plain words

Your body turns very little codeine into its active form, so it likely won't ease your pain. A different pain reliever is usually suggested.

What it means

Greatly reduced morphine formation leading to diminished analgesia.

What the guideline suggests

Avoid codeine use because of possibility of diminished analgesia. If opioid use is warranted, consider a non-tramadol opioid.

FDA drug label

Use with caution See the FDA table (U.S. Food and Drug Administration, opens in a new tab)

In plain words

Your body turns very little codeine into its active form, so it may not relieve your pain as well.

What it means

Results in lower systemic active metabolite concentrations and may result in reduced efficacy.

What the label suggests

No specific dosing change; codeine may be less effective. Refer to FDA labeling.

Also inTylenol #3, Fioricet with Codeine, Ascomp and 15 more

See full details for codeine

CYP2D6Poor metabolizer

CPIC guideline

Consider alternative Evidence: strongRead the guideline (Clinical Pharmacogenetics Implementation Consortium, opens in a new tab)

In plain words

Your body turns very little codeine into its active form, so it likely won't ease your pain. A different pain reliever is usually suggested.

What it means

Greatly reduced morphine formation leading to diminished analgesia.

What the guideline suggests

Avoid codeine use because of possibility of diminished analgesia. If opioid use is warranted, consider a non-tramadol opioid.

FDA drug label

Use with caution See the FDA table (U.S. Food and Drug Administration, opens in a new tab)

In plain words

Your body turns very little codeine into its active form, so it may not relieve your pain as well.

What it means

Results in lower systemic active metabolite concentrations and may result in reduced efficacy.

What the label suggests

No specific dosing change; codeine may be less effective. Refer to FDA labeling.

The tab on top names the gene and your result. Under it is one card for each source that has guidance, and each card has the same parts:

• The source and a link to its guideline or drug label.
• The evidence: strong, moderate or weak, as the source rates it. Some sources, such as the FDA's drug labels, don't rate their evidence.
• In plain words: what your result means for you, which Gene2Rx writes from the source.
• What it means: the source's own words on what your result does to the medication.
• What the guideline suggests (or what the label or the research suggests): its recommendation, in its own words. This is the part a prescriber will want to read.

Where the guidance comes from

The report uses four sources. Each card names its own, so you always know who is speaking.

• CPICClinical Pharmacogenetics Implementation Consortium. Peer-reviewed prescribing guidelines.
• DPWGDutch Pharmacogenetics Working Group. Prescribing guidelines used across Europe.
• FDAU.S. Food and Drug Administration. Pharmacogenetic information in drug labels.
• Gene2RxGene2Rx research summaries. Published studies we summarize where no guideline exists yet.

CPIC and DPWG write prescribing guidelines from the published evidence. The FDA's information comes from drug labels and its table of pharmacogenetic associations. Where no guideline exists yet, Gene2Rx summarizes published studies, and those cards say so. Gene2Rx is not affiliated with or endorsed by CPIC, the FDA or DPWG.

When sources disagree

Look at codeine's two cards again. CPIC says "consider alternative" and FDA says "use with caution". Sources often reach different conclusions, because they weigh the evidence differently or were written at different times. The medication's label follows the most cautious source, here "Consider alternative", and every source keeps its own card so you can see where they differ.

Some medications depend on more than one gene. There are two ways the report shows this.

One table for several genes. Some guidelines read two or more genes together and give one answer for the combination. The tab then joins the genes with a plus sign, and the card says how they were combined. Sertraline reads CYP2C19 and CYP2B6 together:

CYP2C19Intermediate metabolizer+CYP2B6Normal metabolizer

CPIC guideline, both genes together

Evidence: moderateRead the guideline (Clinical Pharmacogenetics Implementation Consortium, opens in a new tab)

In plain words

Your body processes this drug a bit more slowly. You can start at the usual dose, but your doctor may raise it slowly, and a lower ongoing dose may be enough.

What it means

CYP2C19: Reduced metabolism of sertraline to less active compounds when compared to CYP2C19 normal metabolizers. CYP2B6: Normal metabolism of sertraline to less active compounds.

What the guideline suggests

Initiate therapy with recommended starting dose. Consider a slower titration schedule and lower maintenance dose.

From the combined CYP2C19 and CYP2B6 table in CPIC's guideline for serotonin reuptake inhibitor antidepressants.

CPIC reads your CYP2C19 and CYP2B6 results together for sertraline, so this label reflects both genes.

A card for each gene. Other medications have separate guidance for each gene. THC has four genes, each with its own card and its own answer, and the label follows the most cautious one. Its row shows all four genes at a glance:

THCCannabis, Marijuana Use with caution You may be more likely to feel anxious or paranoid on THC. Starting with a lower dose can help.CTAKT1Decreased functionCOMTIntermediate functionCYP2C9Intermediate metabolizerFAAHNormal function

AKT1Decreased function

Gene2Rx research summary

Use with caution Evidence: weakSee the drug page (Gene2Rx research summaries, opens in a new tab)

In plain words

You may be more likely to feel anxious or paranoid on THC. Starting with a lower dose can help.

What it means

One rs2494732 C allele. In a case-control study of first-episode psychosis the variant was not associated with psychosis, cannabis use or frequency of use on its own, but modified the association between cannabis use and psychotic disorder, and acute psychotomimetic symptoms rose with C-allele count in cannabis users. A later study of 720 people found no such association.

What the research suggests

Some research suggests that carriers of this variant may have a moderately higher risk of psychotic-like effects from THC. However these findings are not conclusive. Consider starting at a lower dose and monitoring for psychotic-like effects or avoiding THC altogether.

COMTIntermediate function

Gene2Rx research summary

Use as directed Evidence: weakSee the drug page (Gene2Rx research summaries, opens in a new tab)

In plain words

Your genes point to a typical response to THC, with an average chance of side effects.

What it means

One rs4680 G and one A allele (Val158/Met158). Intermediate COMT activity and average dopamine clearance.

What the research suggests

No COMT-based adjustment. A typical response to THC is expected.

CYP2C9Intermediate metabolizer (activity score 1.5)

Gene2Rx research summary

Use as directed Evidence: weakSee the drug page (Gene2Rx research summaries, opens in a new tab)

In plain words

Your body may break down THC slightly more slowly than average, so effects could feel a little stronger or last a little longer.

What it means

Activity score 1.5 (one decreased-function allele, usually *2). Slightly reduced hydroxylation of THC. In the only published pharmacokinetic study of oral THC by CYP2C9 genotype, *2 status alone did not change THC exposure, so any increase at this activity score is expected to be small.

What the research suggests

Initiate at standard doses. Monitor for increased sedation or psychotropic intensity.

FAAHNormal function

Gene2Rx research summary

Use as directed Evidence: moderateSee the drug page (Gene2Rx research summaries, opens in a new tab)

In plain words

This gene works normally, so THC should affect you in the usual way.

What it means

Two rs324420 C alleles (Pro129). Usual hydrolysis of anandamide and related endocannabinoids, so baseline cannabinoid receptor tone is typical. FAAH does not metabolize THC.

What the research suggests

No FAAH-based adjustment. Response to THC is expected to match population norms.

See full details for THC

For warfarin, the FDA label gives a starting dose range for each combination of CYP2C9 and VKORC1 results, and further genes adjust it. Warfarin's page in the report shows how its estimate was worked out: the label's table with your cell marked, each adjustment, and the estimate beside the typical starting dose.

1. 1

   Start from the dose table

   The FDA label's table gives a starting range from two genes. This VKORC1 result (decreased expression) and CYP2C9 result (*1/*2) give 3-4 mg/day.

   Starting dose by VKORC1 and CYP2C9, mg/day

   VKORC1	CYP2C9 *1/*1	CYP2C9 *1/*2	CYP2C9 *1/*3	CYP2C9 *2/*2	CYP2C9 *2/*3	CYP2C9 *3/*3
   Normal expression (G/G)	5-7	5-7	3-4	3-4	3-4	0.5-2
   Decreased expression (G/A)	5-7	3-4 (this result)	3-4	3-4	0.5-2	0.5-2
   Low expression (A/A)	3-4	3-4	0.5-2	0.5-2	0.5-2	0.5-2

2. 2

   Adjust for CYP4F2 *3: +5-10%

   Because you carry CYP4F2*3 (rs2108622 T), your estimated dose is increased by about 5-10%.

   Low end

   3 + 5% = 3.2 mg/day

   High end

   4 + 10% = 4.4 mg/day

Estimated dose: 3.2-4.4 mg/day (lower than typical starting dose).

The table's starting dose with typical results is 5-7 mg/day.

This uses the FDA label's genotype table in place of the full CPIC dosing algorithm, which also weighs age, weight and other medicines. A clinician sets the actual dose.

An estimate like this is a starting point for a prescriber, who also weighs age, weight, other medications and regular blood tests. It is never a dose to take on your own.

There are three ways to find a medication:

• Search. The search at the top of the summary, and the smaller one in the section bar, find medications by generic or brand name ("Zoloft" finds sertraline), drug classes and genes.
• All medications. The full list, grouped by drug class (26 classes in the example). Filter it by label, for example to see only "Consider alternative", or group it by label instead of class. "Open all" opens every row, which helps before printing. "Browse drug classes" lists every class with a small bar showing its mix of labels.
• By gene. In a gene card or row, the number of medications is a link. It narrows the list to the medications that gene affects.

Each medication and each drug class also has its own page within the report. A medication's page has its genes, every guideline in full, any dose working, what the medication is used for and the others in its class. A class page puts its medications side by side, grouped by label, which is a quick way to see which options suit your results. Try Venlafaxine in the example, or its class, antidepressants.

After key genes and the gene table, the summary ends with:

• Worth discussing with your prescriber: every medication labeled "Consider alternative", grouped by class. If you take or may take any of them, start here.
• Notes that apply to your whole report, such as the anesthesia note above.
• A reminder not to change a dose on your own.

Further down, Genes lists every gene in full: results that differ from the most common one first, then typical results, then genes your data couldn't show. Last comes About this report. It says what the report covers, what your data can and can't show, where the guidance comes from, how your DNA was read, and answers common questions.

"What your data can show" is worth reading once. For DNA from a consumer test such as 23andMe or AncestryDNA, the report fills in positions the chip didn't test by comparing your data with a large reference panel. That works well for common variants but can miss rare ones. CYP2D6 copy number (extra or missing copies of the whole gene) isn't measured from any data type, and it can change CYP2D6 results.

The PDF button at the top of the report offers two printable versions. Neither depends on what you've opened, filtered or searched on screen.

Both PDFs repeat the report's main caution: this is not a clinical test. Results that matter should be confirmed with a clinical-grade test before anyone changes a prescription.

With Gene2Rx Pro, your own report adds a few tools. Without Pro they show a lock, and the example report doesn't show them.

• Report Assistant: ask questions about your report in plain language, for example "What does my report say about sertraline?". It sees your results, not your name or account details.
• Medications you take: add your medications and the report marks them, shows them first in your summary and checks them against each other for interactions that can change how your genes work.
• Medication Selector: for drug classes such as antidepressants or statins, it ranks the options for your genes and says plainly when your genes don't favor any of them.

Gene2Rx reports use the same layout and differ in which medications they cover:

• Full Report: every medication Gene2Rx covers, across all drug classes. The examples in this guide are from a Full Report.
• Psychiatric Report: mental health medications, such as antidepressants, antipsychotics and ADHD medications.
• Starter Report: everyday substances such as caffeine, alcohol and nicotine.

A Psychiatric or Starter Report ends with a list of the drug classes it leaves out and how many medications each adds, so you can see what an upgrade would include. If you entered results from another company's test, such as GeneSight or Genomind, your Panel Report reads only the genes you entered. Every other gene shows as "Not checked".

Your genes don't change, but guidelines do. Each report keeps the guidance that applied when it was made, and its version number is at the top. When a new version is out, your account page offers an update, and What's new lists the changes.

1. 1Check the medications you take now, or may take soon. Use the search, or filter the list.
2. 2Note any labeled "Consider alternative" or "Use with caution", and any "Unable to determine" result for a medication that matters to you.
3. 3Download the Detailed PDF and bring it, or send it ahead of your appointment.
4. 4Ask whether a result should be confirmed with a clinical test before anything changes.

Don't start, stop or change the dose of any medication because of your report without talking to your prescriber first.