Last night Trimethylaminuria was mentioned in a new episode of the popular doctor fiction drama show in the UK, Doc Martin. The series screens at peak evening viewing time on the popular ITV channel. Last nights show (it's first screening), called 'Mother knows best' included a short filler scene where a young man was at the Dr's surgery with a 'fishy smell'. Doc Martin told him he suspected TMAU and asked for a urine sample. That was basically it.
So even though the researcher for the show got their facts confused, perhaps they are right about tyramine and raised pulses with FMO3 deficiency afterall !
Eileen Treacy 2005 Hypertension study in Ireland
2000 paper on FMO3 and tyramine by Cashman, Treacy et al
Consistent with the fact that human drug-metabolizing enzymes have endogenous substrates and are prevalent not as neutral balanced polymorphisms but for their selective advantages, we have previously shown that human FMO3 metabolizes biogenic amines such as tyramine and phenethylamine, resulting in formation of their oxime metabolites. Formation of oxime metabolites generally terminates the pharmacological activity of the parent amine (Lin and Cashman, 1997a,b). Herein, we show that the methionine variant at codon 257 of human FMO3 shows decreased N-oxygenation for the substrate tyramine. Tyramine is an indirectly acting sympathomimetic that exerts its pressor effect through amine uptake into the sympathetic nervous system with release of norepinephrine from synaptic vesicles. It is thus possible that human FMO3 polymorphisms affecting tyramine or other biogenic amine metabolism may predispose humans to variable tolerance to tyramine or other biogenic amine-containing foods and the associated symptoms (Reddy and Hayes, 1989; Stratton et al., 1991).
Quote from Nigel Manning TMAU PDF for Sheffield Children's Hospital
TMAU1 patients may suffer from adverse drug reactions (eg with codeine;
tamoxifen; ketoconazole; nicotine; cimetidine; ranitidine; phenothiazine).
Hypertension may result from ingestion of red wine and cheese (and
chocolate), which produce the neurotransmitter tyramine, another FMO3
dependent compound. Many people suffer from migraines associated with
tyramine containing foods and perhaps FMO3 deficiency may explain some of
these cases, but overall this demonstrates the adverse medical
consequences as well as the odour related psychosocial aspects.
wikipedia : tyramine
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