The Curious Case of the Stubby Thumb


Photo: A BDD thumb (left) and a normal thumb (right)

by Rosa Lin/Medill News Service

“What happened to your thumb?”

“Did you accidentally smash it in the door?”

A thumb was outstretched in the circle of sixth-graders. It had a most peculiar shape, being relatively thin and normal near the base, and then suddenly capped off with a bulbous, short tip, reminiscent of a slightly flattened pearl onion.

The thumb belonged to 10-year old me.  And I was showing it off proudly among my bemused friends.

“See, the other one's like this too!” I stretched out its equally short and bulbous sister. Everyone gaped, laughed, and held the thumb up for inspection.

“You must've bitten your fingernails too often when you were little!”

“Did you jam your thumb playing basketball?”

Why, no, I was born this way. If you're like me, you probably fielded these questions in your youth and wondered whether anybody else in the world has thumbs like yours.

Wonder no more – these thumbs are known in scientific circles as brachydactyly type D, a type of thumb characterized by a shortened distal phalanx (the bone at the tip of the digit) – and we are about to plumb the history, prevalence, myths and genetic basis behind these thumbs.

Most people have a straight, upright thumb, with a nail bed equal to or longer than the nails on their fingers. Some people have a “hitchhiker's thumb” where the tip can bend back almost 90 degrees. Finally, a few people – from 0.10 to 3 percent of a population – have a shortened thumb, a feature colloquially known as club thumb, stub thumb, toe thumb, potter's thumb, hammer thumb and most unappealingly, murderer’s thumb. Fortunately the thumb has been christened neutrally by scientists as brachydactyly type D, so henceforth we shall stick with the designation BDD.

BDD was first characterized by fortune tellers practicing palmistry. According to's page on Indian palmistry:

"The Murderer's Thumb Unveiled - The clubbed thumb was traditionally called the 'murderer's thumb' denoting the powerful temper of those who carried it. This thumb has a short first phalange (section) and is broad. The tip of the thumb is fleshy and the thumbnail is short and broad. According to those who know, people with clubbed thumbs [however] are strong willed and can control their emotions."

Such a description is rather more palatable than's take:

"This thumb is in a shape of a club. People possessing this type of thumb are animalistic in nature and thought system. They bear brutality of Elementary type. They can harm or murder out of callousness. They lack premeditation and depth."

Ouch! This leads the meeker among the BDD carriers to wonder: why such a dark reputation among chirologists? For the record, chirologists are fortunetellers.

“When these [traits] started getting studied in the late 19th century … there was a push to link [physiological] traits with personality traits. There's no real scientific connection between BDD and any personality trait though,” said Dr. Nathaniel H. Robin, an active clinical genetics practitioner and professor at University of Alabama at Birmingham, who authored a paper on BDD.

BDD is so named because it is one of many traits of brachydactyly, the term given for shortened fingers and toes due to underdeveloped bones in hands and feet. For example, there is brachydactyly type A, where middle phalanges of one, several, or all of the fingers and/or toes are shortened; brachydactyly type B, where distal phalanges and nails of the fingers and/or toes are small or absent; and so forth up to type E. Usually brachydactyly is an isolated trait, meaning that it is not associated with other medical conditions and is generally harmless.

Contrary to what many people with BDD think, BDD “is a fairly common trait,” Robin said. It stays in the population because “it's a benign variant,” meaning it is neither advantageous nor detrimental to those that express the trait.

According to "Abnormal Skeletal Phenotypes," published in 2005 by Alessandro Castriota-Scanderbeg and Bruno Dallapiccola, two prominent radiologists, BDD occurs in 0.4 percent of whites and 0.1 percent of blacks in the United States, with a higher incidence in Israel (1.6 percent of Jews, 3 percent of Arabs) and Japan. In three-quarters of cases, BDD occurs bilaterally, which means it appears on both thumbs, while in the rest of the cases it only appears on one thumb, with the other thumb normal.

There is also a skew among genders. The pioneering human geneticist Julia Bell found in a 1951 study that 60 percent of those affected with BDD were female, while 40 percent were male. The geneticist Robert Stecher confirmed the preponderance for females in a 1957 study. The reason for this may be due to incomplete penetrance, a genetic term that means that a trait fails to express itself even though a person carries the necessary genes. In the BDD case, there is evidence to suggest that the trait has complete penetrance in females and incomplete penetrance in males. BDD is also an autosomal dominant gene, which means a person only needs to inherit it from one parent in order to express the trait.

In the past 10 years, scientists have been able to gain more insight into the genetic basis of BDD. In a 2003 study published in The American Journal of Human Genetics, researchers reported that two mutations in the gene HOXD13 may contribute to BDD.

So who has this trait? One of its most famous carriers is Megan Fox, an actress starring in the "Transformers" movies. She carries the trait on only one thumb, signaling incomplete penetrance. Due to her profile as a celebrity, discovery of her BDD thumb was highly publicized. Russian author and Nobel laureate Alexander Solzhenitsyn is also purported to have at least one BDD thumb. Other people with the trait include: Malin Akerman (US actress), Tory Mussett (Australian actress), Ashley Lynn Cafagna (US actress), and Kristen van Der Noot (Germany DJ and model).

The most speculated of BDD carriers, however, is past European royalty. Despite valiant efforts, I did not find which royals exactly are implicated, so we shall briefly suspend any curiosity along those lines. The European royalty had higher than normal incidence of inbreeding due to a desire to keep their bloodlines “pure.” This resulted in any abnormality or mutation, such as hemophilia, reappearing in higher rates in descendents, instead of being flushed out by a set of significantly different genes. BDD is claimed by some to be a marker of descent from European royalty. However, as BDD occurs all around the world and is both the result of inheritance and random mutation, this, if true, would only apply to a small subset of those with BDD.

“I have no idea” if BDD is linked to European royalty, Robin said. “It may be true – I have no idea.”

At least I have an idea whether mine is linked to European royalty - I'm 100 percent East Asian!




  I have both thumbs which

  I have both thumbs which are 'hammerheaded' I am 51 and thought i was the only one with these thumbs. My Grandmother had them from my mother's side but my brother and sister have normal thumbs. I have always hidden them as i was teased with them starting from High school. My husband calls them my toe thumbs! When i had my 2 sons the first thing i asked was do they have my thumbs! I am so glad i am not alone now that i've came across this site. Thanks.

I am 56 years old and was

I am 56 years old and was told my whole life that my stumpy thumb on my left hand was from sucking my thumb as a child. I stumbled upon a photo of Megan Fox and had a "AHA" moment. I now feel proud of my anomoly and will educate my family of it's being. I am proud to be a part of the STUMP club!

I've always felt ashamed and

I've always felt ashamed and very "different" on account of both my thumbs, the left is worse and both are off, abnormal. In fact both those words describe me personally. Just my two cents. A specialist looked at my other digits however and says they are clubbed. I can't conceptualize that nor get his meaning even when he compared mine to his...but I may have a serious heart/pulmonary problem- I won't know for a while still yet, but for years I've had chest pains and breathing difficulties. They are even tougher now. I'm both Eastern Euro Jewish as well as Arabic ancestry (Dad's Jewish, Mom Syrian), doubt I'm "Roya;" much less Imperial anywhere anywhere!

I have one such thumb and

I have one such thumb and never knew anyone with the condition. I consider myself African American but my bloodline is so mixed with American Indian, Arab, UK, African that it is impossible to say. My mom and dad's had me late and their parents were old when they were born so I never knew my granddads on either side. However, I don't remember ever seeing that on the beautiful feminie hands of the other women. I was the only one. Sounds very interesting but a puzzle I doubt can be solved. Happy to know I am part of a distinguished international "club".

I inherited my club thumbs

I inherited my club thumbs from my mother. My aunt, her twin, also has the trait as do 2 of their sisters whom I believe was passed the trait by my grandmother.

I was in the cafeteria at work recently and saw another woman with club thumbs. I said "I'm sorry, you're going to think I'm odd...but can I show you something?" And I stuck out my thumbs for her perusal. She was shocked because, really, how often do we see someome else that understands that particular uniqueness? :)

Oh wow, seriously, me and my

Oh wow, seriously, me and my pair of ugly thumbs or UT are glad that we are not alone, I live in Scotland and ive only

ever seen one or two other people with suspiscously short thumbs but I was too embarassed to point it out and claim kinship

as I have always hidden them out of shame and didnt want to embaress them.

We should start a UT society, i wish I could be proud but people always look at my UT's with horror and repulsion........

It's pretty funny to read how

It's pretty funny to read how rare it actually is.

both my thumbs BDD, identical and can bend it 90 degrees.
I'm also 100% European so the thought of it being linked to royalty is awesome since the country i'm currently living in still has a Queen.

How nice to meet you all.  I

How nice to meet you all.  I had no idea you existed or that I belonged to such a club (no pun intended) or that my two thumbs and two big toes could be identified beyond the negative handles they were given in my youth.  I am in my 60s now having spent most of my life feeling a little selfconscious and sometimes unlovely.  Given I am also indigenous (read minority) to NZ my strange looking didgets caused additional sniggering at school which just made me feel even more isolated.  Can't say I ever felt proud of them - I wanted to wear nail polish, jandals and bare feet at events but felt too selfconscious.  Fortunately I am over all that now.

Out of a family of 10 one brother also had these didgets and of my 3 children, my youngest son also. However, my grandchildren have inherited one of other of the features!  Their parents blame me...  Thanks for the article - it was a hoot! 



It’s so nice to learn that so many people are out there and “special” like me.

I am also having two BDD thumbs which have given me a lot's of embarrassment during my youth as some kids would tease me about them. I did not know if anyone else had same thumbs until my brother has married a girl with same shape thumbs. What a chance of that happening!?

A few years back I had to visit a hand specialist (reputable hospital in Oxford) for some other had issue I had and to my surprise hand specialist was surprised to see my thumbs. He has never seen them or heard about their existence. What a hand specialist!!??

I have just returned from a cruise in Med where I have met an old lady that had same shape thumbs. After showing her my thumbs she was so pleased to realise that she was not the only one with thumbs like hers. She believed it was only her that had them and she has always tried to hide them in social surroundings. Talking to her about her origin and I have found that one of her grandparents is from Poland and the other was from Odessa in Ukraine. What a coincidence to meet someone with same BDD thumbs on cruise ship and sitting next to that person? Amazing!

I have to say that I am not aware that anyone in my close family had thumbs like mine and neither of two of my children are having thumbs like mine either.



I have only come across 2

I have only come across 2 other people in over a half century of my life who have BDD. One was male and the other was female. None of my relatives on either side of my family for at least 2 previous generations had them, nor could any of my elders recall anyone farther back in my family tree who had them, either. I have 3 sons of my own, none of whom have BDD, nor do any of my cousins or second cousins. I'm the only one.

I did find it rather curious that this article mentions the possibility of a connection to European royalty, considering both my maternal and paternal grandmothers were European. One was born and raised in Brussels; the other had an unusual accent and was always going on about how "we have the blood of kings", complained a little too much about "foreigners" here in the US and claimed to have been "from Milwaukie, WI". The ONLY documented evidence I could find when doing research on my family history to anyone with my maiden name traced back to my paternal great-grandfather from Bohemia (which was a kingdom during the Holy Roman Empire up until the early 15th century). Interestingly, the only documentation matching my paternal grandmother was her social security records which only date back to 1973. The woman had such an extremely royal mentality; she had the best of everything and yet she was never truly happy because it was never good enough; her life makes for a real mystery. Perhaps there is, at least in my own BDD case, some truth to the speculated connection between BDD and royal bloodlines although I haven't been able to connect all of the dots yet. Genetic out-crossing within at least the past couple of centuries and a complete lack of recent relatives having BDD seems to indicate that my BDD comes from a very recessive gene, indeed.

Thank you so much for putting this article together and shedding some light on BDD and the variety of perspectives which have been attached to it!


I am 57 years old and it's

I am 57 years old and it's taken all these years to find out why my thumbs are the way they are. I have only ever seen two people during my life with BDD thumbs. One was my seventh form  chemistry teacher so that was a while ago now. I found it interesting to know that the trait only came down through one side of the family so I am now off to question all my relatives. By the way I found out about this from a recent episode of Elementary on TV where Watson picked up the perpetrator because of his BDD thumb. 

I remember that ever since I

I remember that ever since I was a child other kids would often ask about why I had both of my thumbs like that: did I suck or nib them too much? Did I have an accident? Adults would ask too, but it was with honest curiosity and maybe a little mockingly (from the kids) but I truly didn't care and I still don't. I find them useful and quite cute in their own unique way. Nobody in my family, inmediate or distant has these thumbs and I'm too much like my dad to even claim I was from the milkman (hahahah) so I must be the first in the family with the mutation. The only pain is trying to text fast on a touch screen!

I'm 26 years old girl from

I'm 26 years old girl from Indonesia. I'm so glad that I bumped into this article. I've never met anyone with BDD (only saw megan fox's) and both of my thumbs are symmetrically BDD. I never had any problem with them (to be quite honest, they make me feel unique) the only 'problem' that bothers me sometimes is how some people react to it! I always try to laugh with them and proudly show them, but sometimes they over-reacting (and it takes time to explain it to them) :P so I have to admit that over the years, I always keep my nails long to 'blend in' just to save time hahaha.. When I was a kid, I asked my mum about it and she told me maybe because I sucked my thumbs when I was in her tummy, because neither my mum nor my dad has it. Thank you so much for this article and.... hello everyone! *thumbs up*

I've been a teacher for more

I've been a teacher for more than 15 years and there have been at least 10 students with thumbs like mine. They were always the ones who noticed my thumbs and their happiness was enormous when they finally found someone else with super cool thumbs.

I'm Australian and in my

I'm Australian and in my sixties.  I've had two 'fat' thumbs all my life and have not come across anyone else with it.  I was watching an episode of "Elementary" last night when one of the characters referred to 'clubbed thumbs' and the formal name of the condition.  Despite having been the subject of continuous curiosity and funny/peculiar comments by other kids when I was growing up and many adults it never occurred to  me that it was a named condition.  It's never been a problem for me but I've always used a stylus to text.  Perhaps that's why. I did give up on getting manicures as the manicurist always seemed baffled with what to do with my thumbs.  Just paint them I thought but that was just too obvious.  One even suggested that she leave an unpainted strip on either side of my nail to 'disguise' it.  As if that would make any difference.  Now that the name of the condition has been outed in the entertainment media perhaps more people will come out of the closet.

They use a big toe artificial

They use a big toe artificial nail for mine, and it helps my shyness about mine quite a bit. Once they just used two thumbnails and made it work. What bothered me is how much the techs. laughed and talking in their language about it amongst each other. I laughed too, just because they were so intertaining to me about it when they saw it. I've run across lots of people with it. And have always felt self conscience about it. My first child of 8 has it as well on one thumb. None of our grandkids have it so far, and we have 21 to this date...LOL

The branch of royalty

The branch of royalty associated with this type of thumb is the Hungarian Plantagenets.  The Austrian line has the funnel lip, but the Hungarians have the thumb. 

Very cool article!  My left

Very cool article!  My left thumb is BDD and my right in normal.  I'm half Japanese and Korean, but I think I got it from my Korean side.  My nephew has 2 BDD thumbs and my daughter's big toes are "stumpy" as well.  I always thought it was due to sucking my thumb, but this makes more sense.

I grew up embarrassed of it at an early age.  I remember hiding it when playing video games amongst other things. Other than my immediate family, my wife is the first person I've shared my secret with.  Now I'm 37 and could care less who sees it.  Thanks to this message board I feel more normal!

WOW how great thru the

WOW how great thru the internet to find out Im normal and there's others out there like me.I have them on both my hands and my big toes.Not many people notice.It doesnt stop me getting on with life.I think we're special ♥

My hammer thumb has a lot of

My hammer thumb has a lot of problems. First, all of my reletives from my dad's side have it. Second, I used to smash it all the time accietently. I enjoy my thumb because it reminds me of two little siblings having fun in a playground. When I was in 4th grade, I woke up, and found that my thumb was cracking everytime it would lean on my fore finger. After 2 years, I was palying volleyball, and this girl hit into my other thumb. I couldn't move it so I had to do a surgery and wear this cast thing for a week. Now, I'm 19, and still cracks!

My daughter has this on both

My daughter has this on both thumbs, although she's the only person on both sides of my family that I've ever seen it in. I used to think it was due to something I did, or didn't do, during pregnancy. It's not much of a nuisance for her, except getting her nails done at a salon, but I'm rather relieved it's not directly related to my pregnancy.

I have two clubbed thumbs and

I have two clubbed thumbs and the more markedly so on the right hand. The very strong nail and shortness on the right has proved a great advantage in my banjo-picking technique. Not only for the strength of the nail, also for the fact that it tucks in naturally behing my index and ring fingers.

Today, i found out that my

Today, i found out that my thumb has a name after stumbling across this site.  My maternal grandmother had one and I am the only one in the family, besides her, to have this thumb.  I'm 62 and have 5 children and one grandson and none of them have this trait.  When I was little, my grandmother told me that when she was a young woman a doctor noticed her thumb and told her she would always "fall on her feet".  She always did, as have I so maybe there is soomething in what the doctor said.

Hi, when i see all these

Hi, when i see all these comments about people being proud of their BDD thumbs, got them too, i wonder how u can be proud of it? Any tips? Im getting picked on in school time to time :(. I cry myself to sleep sometimes because of them :( just wanna be normal... Im also colorblind, crosseyed, longsighted and flatfooted, so having these thumbs makes me feel even more abnormal, and not in a good way. Pls tell me some tricks to like my thumbs :,(

I have a club thumb. Only

I have a club thumb. Only just found out that it actually has a name. Literally 10 minutes ago. Im glad that i am not on my own and didnt realise that there was alot of people with the same thing. I used to let it get too me when i was younger and always hide my thumb for photographs. Which i still do occasionally but that is through old habbits. There is only my nan ( dads mum) who had one that i know about . Im me and cant or dont want to change anything. Xxx

I have two stubby thumbs just

I have two stubby thumbs just like my dad's dad. I don't remember people taking notice. It also never occurred to me to be embarrassed. I'm actually very proud of my stubby thumbs and believe that it has helped to develop my sense of humor, due to the fact that I thought it was a male trait. It's good to know that there are others with freaky thumbs like mine!

I have one of these thumbs..

I have one of these thumbs.. it's my left one and I have always been a bit embarrased about it for as long as I can remember and my mum said she didn't even notice it while I was growing up lol. Glad to know I am not the only one even though I still hate it haha.

Seamstress thumbs. Absolutely

Seamstress thumbs. Absolutely! My wife (of several decades) has them. I never noticed until she told me. She sewed all the daughters clothes, uniforms (even changed the school uniforms when they had glitches). Made jackets for me over the years that persons wanted to know where I got them as they wanted them also. She sewed for and dressed the opera singers for years. Made doll clothes (Barbie) that after many years when a yard sale was had to clear out the house the first lady who saw them bought them all.

Whatever other name they may have, in this family they will always be known as, 'Seamstress Thumbs".  

My right thumb is one of

My right thumb is one of these BDD thumbs. Although it's very obvious, especially when side by side with my left thumb, hardly anyone has ever noticed it until I've pointed it out. My Mom had a thumb like mine, and she always said it was because she'd slammed it in a car door when she was a young girl. I think she really believed that  became convinced it was hereditary when I grew up  had a thumb just like hers.

I have 2 BDD thumbs. All my

I have 2 BDD thumbs. All my life I have been embarrassed about them, I panic when I feel someone looking at them. I've always envied other women with beautiful hands and nails. I actually work in healthcare and am glad I have to wear gloves all the time. I was glad both my girls did not have them. My great aunt had them. So glad there are others!

Even though I have a really

Even though I have a really short thumb, but other than playing one instrument from the chinese culture it didn't really effect much. So remember you are still perfect the way your are and all of us can bare with this thumb until we die. :) 

Even though I have a really

Even though I have a really short thumb, but other than playing one instrument from the chinese culture it didn't really effect much. So remember you are still perfect the way your are and all of us can bare with this thumb until we die. :) 

 I have BDD on the right

 I have BDD on the right thumb only. My first born son has it as well. His children do not. I had 8 kids, and only my first was born has it. I haven't seen it on any of the 21 grandkids yet. Mine was inherited from my Mother's Father, who had both thumbs involved and who's parents immigrated to America from Switzerland and France. A couple of my Grandfather's brothers had it as well, including his Father. Some with both thumbs involved and some with only one. Mine helped me with my tennis grip temendously, and helps me to open jars that others cannot get open! It's extremely strong. To have artificial nails applied, they have to use a "big toe nail" for my thumb. It seems to camoflage this BDD quite a bit by having my nails done. 

I too have thumbs like this.

I too have thumbs like this. Funny that European royalty was mentioned. Hemophilia runs in my family. I'm a carrier and my son has Hemophilia. Which is also linked to European royalty. I always wondered why my thumbs were so different than anyone else in my family. 


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