Posted on September 19, 2011

The Gene Disorder That Makes You Smell

Amy Norton, The Star, September 16, 2011

For some people with troublesome, unexplained body odor, an uncommon genetic disorder once known as “fish-odor syndrome” may be to blame, according to a study.

The condition, known clinically as trimethylaminuria, is caused by emitting excessive amounts of the compound trimethylamine (TMA). TMA is produced when people digest foods rich in a substance called choline–including saltwater fish, eggs, liver and certain legumes, such as soy and kidney beans.

“Individuals with the metabolic disorder trimethylaminuria may sporadically produce malodors despite good hygiene,” wrote study leader Paul Wise, at Monell Chemical Senses Center in Philadelphia, in the American Journal of Medicine.


Trimethylaminuria is caused by defects in a gene known as FMO3, which hinder the body’s ability to metabolize TMA and turn it into odor-free compounds.


For someone to have the disorder, he or she must inherit a defective copy of the FMO3 gene from both parents, who themselves would be unaffected “carriers.” Of course, if either of the parents had the disorder, they would also pass it on.

Studies in the UK have estimated that up to 1 percent of white people carry a flawed copy of FMO3, with some ethnic groups–including people from Ecuador and New Guinea–having a higher rate.

For the current study, Wise and his colleagues looked at how often trimethylaminuria was diagnosed in patients who came to Monell seeking help for unexplained, persistent body odor.


[Editor’s Note: Studies on racial differences in the prevalence of trimethylaminuria are available here and here.]

28 responses to “The Gene Disorder That Makes You Smell”

  1. Anonymous says:

    It’s not a disorder- it’s a gift from nature that tell you to get the heck away from whatever smells like that.

    Danger, danger, run, run faster, Diversity on the loose!

  2. 4 teh lulz says:

    Fish odor is an artificial construct… LOL!

  3. AnalogMan says:

    Racial differences in body odour? Hell, yes; hadn’t you noticed?

    My racist dog’s nose knows the difference well. And it’s not just an occasional fishy-smelling individual.

  4. Anonymous says:

    I wonder if blacks are more likely to carry this gene as well. One common negative stereotype associated with them is foul odors.

  5. W. Smith says:

    Get the rumor started that trimethylaminuria was an African god of virility and watch the name pop up in the next generation of urban youths.

  6. underdog says:

    After a cursory skim of this article, the only thing that I can say regarding same is that I am no odor scientist by any stretch of the imagination, but Westerners do emit an offensive body odor to Orientals due to comparatively high red meat consumption.

  7. Dave says:

    1968 – I was a 10 year old transplant from all white Follansbee West Virginia to a more “mixed” Halifax County Virginia. I tried to make friends with the local black kids by asking them questions about their thoughts on white people. I’ll never forget when John Scott told me that “White People’s wet hair smells like a wet chicken!” Being less than a typical accommodating liberal, I said that it was better to smell like a wet chicken than to wreak like a rotting dead animal such as black people. Needless to say, we had a fight! I busted his nose and that was the last of our “civil” banter!

  8. tony Soprano says:

    I recall that according to John R. Baker that the races do smell different.That could give you the idea we should not intermarry.It is nature telling us something.

  9. Anonymous says:

    The Baker reference does not merely highlight the difference in

    Black / White body odor but how unbearably intense such odor can

    be. I am at monthly intervals on campus at a major inland USA university that has a high incidence of students from China. One sees a small degree of White male/Chinese female social pairing. I have yet to see a single instance of Black/Chinese pairing and almost no instance of Chinese having any physical proximity to Blacks for any appreciable period of time. Reportedly, the Chinese find Blacks often unpleasantly smelly. The Chinese are educated in a yet nominally Marxist nation and have no encouragement in their pre-university schooling to be biologically realistic about race.

  10. Ben says:

    @ 3

    I believe the same is said about us as well…

    I’m surprised that no one here knew that apocrine glands are different…

  11. Anonymous says:

    Observation suggests that a noteworthy part of the Black body odor

    problem may be the “g” factor. What passes for diet in America generally and in particular what characterizes so much observable Black “gulp and go” food intake–this is a very important exacerbation to whatever is written into the genes. From an evolutionary standpoint, Blacks are “unfavored and long away from home” when facing what’s on the paper plate in America…and clueless.

  12. rockman says:

    during WWII the allies developed a chemical that mimiced body oder. gave it the code name “Who,me” and would put it on the clothes of axis diplomats and other enemy officals causing them to smell badly. It stands to reason that different races would smell different. I recall a young man in college that I could not stand to be around because of the odd way he smelled. the smell roused my anger and I would wonder what the hell he was wearing.

  13. Anonymous says:

    6 — underdog wrote at 7:59 PM on September 19:

    After a cursory skim of this article, the only thing that I can say regarding same is that I am no odor scientist by any stretch of the imagination, but Westerners do emit an offensive body odor to Orientals due to comparatively high red meat consumption.


    REALLY? From the article.

    The condition, known clinically as trimethylaminuria, is caused by emitting excessive amounts of the compound trimethylamine (TMA). TMA is produced when people digest foods rich in a substance called choline—including saltwater fish, eggs, liver and certain legumes, such as soy and kidney beans.


    Sounds to me like red meat is not even mentioned, underdog.

    As for Orientals not “smelling bad”, I beg to differ. They DO smell bad.

  14. Anonymous says:

    Not to sound gross but everyone has a different odor. Even the smell of what we eliminate is unique. Similar but unique! All it takes is an understanding of organic matter.

  15. john says:

    I understand that blacks emit more waste from they sweat glands,and less from they kidneys,as compared to us. Maybe thats part of why they have so much kidney trouble later in life. That may explain the “musky odor” often encountered.

  16. boreas pearce AE says:

    Before my parents sent me to a White Flight private academy in Dixieland, they naively sent me to our local public school. One of my most profound memories in life is that of the first afternoon I got on the public school bus and was hit by the most noxious fumes of concentrated Africanism imaginable.

    Soon thereafter, I was safely enrolled in a Whites Only private school and never sat next to another one of the blacks for the next several glorious years of my life. I’ve been firmly committed to anti-Diversity ever since that day after school when I encountered one of the horrifying sensate manifestations of Diversity.

    “Prejudice renders a man’s virtue his habit, not a series of unconnected acts. Through just prejudice, a man’s duty becomes a part of his nature.” Edmund Burke

    Amen! Thank God for differences and the native smells of Africa!

  17. ProudtobeWhite says:

    Must be that cheap aftershave some blacks use: “Eau de doo da dey.”

  18. Walt says:

    Hello #7

    Reminds me of the old football chant, “Hit’m again, hit’m agian, harder, harder.

  19. DavidR says:

    The renal systems of African blacks lack the capacity to filter out uric acid that Caucasians and Asians do. A certain percentage of that uric acid in blacks is emitted as blood gasses through the skin.

    Hence the slightly urine-like odor…

  20. South African says:

    They smell different than us. And not due to aftershave or underarm or showering or more hygienic conditions or the food they eat.

  21. AlmostMusicPhD says:

    I remember mentioning to a ‘Diversity Official’ in the Tier 1 East Coast, private moneybags university I tuaght in, when I was called on the carpet for making some comment (to an “Afreakin-Amurrican” student, about how different races’ physiognomies mean different emphases in training for musical careers, that ‘that was just a racist statement.” I didn’t have the corroborative evidence then, but I do now. And your site told me about Avdeyev’s “Raciology” which is firmly in my bookcase now….

    But, all of this ‘discussion’ sounds as ‘racist’ to me, (and I concur with you all!) as did my statement to that University Diversicrat…. so we have a lot of work to do.

    But I do remember my Parochial School 8th Grade teacher. (who was black, and smoked cigars) It was astounding for me to find out, at 13, in my first contact with a black, that his skin just ‘stank’ – no matter WHAT he did. And it turned me off to Blacks for some time. Reading that others noted this, I am glad to have my opinions confirmed. I just thought for forty years, I was merely being ‘racist’ instead of knowing that “… a rose by any other name” still has to be a ROSE, to ‘smell as sweet!’

  22. Anonymous says:

    i read in Erectus Walks Amongst Us that blacks have more urea in their sweat.

  23. Anonymous says:

    The topic of racial difference in odor is given a chapter in the

    great text RACE by the late Oxford University Professor John R.

    Baker (1974/ reprinted 1981).

  24. Anonymous says:

    Francis Galton hypothesized that suitable dog breeds might be

    trained to diagnose (identify) physical disorders. I have never

    heard of any record of it being tried–even in rural veterinary

    medicine in an earlier America.

  25. Anonymous says:

    An element of delu-sphere in America is body odor. In frontier

    America people often went for several days without bathing but , absent illness, generally did not have repellant body odor by

    virtue of lots of fresh water consumption in conjunction with physical activity and a diet shy of processed foods, etc., and by airing out clothing at night, stringently washing clothing, applying vinegar to odor zones, etc. In “our” bubble world,

    a conformity of standardized soap and deodorant not merely obscures many useful natural odors but seems over time to make

    unnatural anything that does not smell like, say, Lever Brothers

    or Proctor and Gamble. Don’t tell Morri$ Dee$ he should launch


  26. white is right, black is whack says:

    I’ve noticed this, too. Why is this?

  27. Anonymous says:

    Re 18

    The folklore of many cultures report dogs having an uncanny ability to discriminate by smell the persons in a village who

    are otherwise known to humans in the community to be asocial/psychotic. Given the very strong biological basis of some major mental disorders, it is not implausible. Man’s bigot? or

    Nature’s gift?

  28. Anonymous says:

    Some small extent of smell based “us/them” signals necessarily

    concern something that is an important part of the miracle of human adaptation by way of evolution–namely, the approximately

    four day, monthly seepage away of an unused (non impregnated)

    uterine lining in order to become, yet again, motherhood ready.

    Having seen in my youth the occasional unobjectionable use of chewing tobacco in proper settings ( using a large flannel “handkerchief” to lip seep tobacco saliva ), I was informed that

    women readily suggested this accommodation. In either case, lip seepage from above or below, a flannel cloth folded over and folded over & over, provides in the matter of menses a clear

    indication of the sequence and amount of discharge. The obvious medical safeguard value of this seems totally unregarded in favor of a vast shelf space of “feminine hygiene” products. Smell terror appears to have won over and against rational tolerance. How can an intelligent young woman be expected to be other than a creationist? Who could believe males could have endured women that didn’t have the contemporary “gift$” of feminine hygiene product$?