News & Views on Systemic Body Odor and Halitosis such as trimethylaminuria TMAU. If you have fecal odors or bowel odors it may be metabolic/systemic

16 October 2022

FMO3 Malodor / TMAU : list of tests from good Metabolic Unit / Genetics Clinic

last update : Oct22

Tests a TMAU patient (correct disorder name - FMO3 Malodor) should look to get from a Metabolic Unit visit, or from a Geneticist. 

imho this is a list of tests that Metabolic Units or Geneticists should use for patients referred for suspected 'TMAU' (imho proper disorder name : FMO3 MALODOR (mostly sulfides)).
You have a right to ask for these tests. If refused then offer to pay.
If still refused then write a politician.

If Dr feels they can't order for free, then let the patient pay.

1. TMAU urine test (Only spots severe's ... rarish) : CHOLINE LOAD (not fish).
note. Choline relies on TMA-bacteria being present.
Fish contains TMAO, so may give artificial TMAO boost, or TMAO may be broken to TMA. 
Choline load is better than trying to mimic diet-choline load.

2. If Choline-load TMAU urine test is -ve, then give TMA LOAD TMAU urine test (600mg TMA ?).
This is the 'carrier' test, but many carriers are actually 'transient sufferers'.

note : author has little confidence in TMAU urine test. Don't know why. Maybe TMA is not best biomarker ?
It's maybe more likely that FMO3-sulfides are better biomarkers, but no such test available yet (write politicians about it).
e.g. Dimethyldisulfide, Methanethiol etc.

3. Choline blood test
Theory : TMA-bacteria destroys diet choline. patient may be long-term very choline deficient ?
Will then be put on low-choline diet, making it worse.
Choline is not currently monitored yet is important nutrient, especially against NAFLD.
We can all ask at Dr visits for this, so they may find a source.

Choline injection
As diet choline is destroyed by TMA-bacteria, the patient may need a choline injection to avoid the TMA-bacteria.

4. FMO3 gene test
This should be the main test. More important than TMAU urine test.
If Dr won't order, then offer to pay. Write to politicians etc.
Most 'mild' cases will probably be snp-heterozygote-compounders.
Clinical FMO3 test only tests the 532 amino acid code. It does not test introns, promoter region etc

Geneticists : look out for HAPLOTYPES !!
FMO3*2 allele, previously described as the *Hap allele

Consumer Genome test is better (to get full info on FMO3 gene, code and introns etc).
Two known consumer WGS testers : Nebula Genomics & Dante (Italy).
These labs are better than health-clinic DNA testing imho.
Health DNA tests only give geneticist interpretation, not the full data.
Consumer WGS tests give you the full data (your genome),

5. Liver scan 
Choline is important to avoid NAFLD. So a liver scan for fatty liver is appropriate.
If Dr won't order, then offer to pay. 

Other possible 'indirect' tests (that Drs won't order ?) :
Vits and mins (like B vits).
Leaky gut.
SIBO test.

Currently we are stuck with diagnosis Trimethylaminuria, from trimethylamine, which has a rotting fish smell. Imho this smell only seems to occur in severe cases.
Most probably have 'FMO3 Malodor' where they smell of any FMO3 substrate, probably usually sulfides (from the gut).
We need to move on from the 'TMAU' diagnosis. Mention it to your Dr, write politicians etc.
Correct disorder name is probably 'FMO3 MALODOR' and other biomarkers are needed (e.g. sulfides).

Speculative Note : it may turn out TMA is still the main 'FMO3 load', but the person still doesn't smell of fish. Perhaps TMA fills the FMO3-bucket but the sulfides spill over and are more potent.  
It may even be 'chronic choline deficiency malodor' (unlikely, but needs ruling out).

Any test is better than no test

Show this to Drs / politicians

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Update Aug 17 :
Genos is back with it's EXOME test

Note :
Exome/Genome testing may be better option than single gene testing.

See this post : link

Note : Genos Exome Testing.

Exome testing is almost the same price now as single gene testing. Also Genos is consumer friendly, which standard DNA labs are not.

So the blog offer to test solely for FMO3 is almost obsolete, and so no longer offered.

Does Genos fully sequence FMO3 gene ?

At the moment it is not clear, but hoped this will become clear over the next few months

Note : possible 'wild west' way of testing FMO3
Use an ancestry dna site and rummage through the raw data

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