Although human beings are mostly symmetrical along the vertical axis, I know there are a couple exceptions – the heart is slightly to the left, the stomach curves (IIRC) to the right, there are probably a few other examples I’m not aware of. Anyway, is it possible for someone to be born “backwards,” that is, with their heart slightly to the right, stomach curving to the left, etc? And if so, are there any health issues associated with this condition, or does everything function normally? I assume it would be extremely unusual for someone to be born with such a dramatic genetic abnormality and without additional abnormalities that would pose serious health risks.
I know *of *it, although I don’t really know anything about it. It’s called situs inversus. It sounds like there aren’t any associated conditions or complications, aside from the confusion it can cause in diagnosis, the difficulties in organ transplantation, and so on.
ETA: Apparently, there is an association with heart defects:
It also says, though, that situs inversus with levocardia is a much rarer condition.
I had an uncle (through marriage) who had *situs inversus. *Nobody knew about it until he was shot in the left side of his body, and the surgeon discovered the condition. There are family members who still believe that the bullet caused his heart to jump from the left to the right side. :rolleyes:
For the record, it wasn’t just his heart; his entire body was a mirror image of the way most bodies are. And the condition kept him out of World War II.
This is certainly possible. The medical term is situs inversus.
I remember reading about this in Jack London’s The Assassination Bureau, Ltd when I was a kid and being completely taken aback by the concept. A character survived a gunshot wound because of this condition.
Is it true that some twins have their internal organs as a mirror image of their sibling? ( There was a Lord Peter Wimsey short story that was based on this concept)
There is a claim in a Dorothy Sayers short story I read, which may or may not have any basis, that “reversed” persons are nearly always the result of a twinning process. Supposedly, in utero they have a mirror twin that is not “reversed”. The story also says that sometimes the “unreversed” twin doesn’t develop and get born, so the “reverse” twin might not have a living twin sibling. This sets off a bit of a bullshit alarm, since how would you prove that there was once a missing “unreversed” twin.
I post for what it’s worth, which isn’t much come to think of it.
I’ve seen documentaries that featured several different people whose knees were backwards, sorta like a birds. And, yes, I know that that joint is actually analogous to our ankle
Fascinating! I’m surprised that complications are unusual, and that it’s not usually discovered early on, say, the first time a pediatrician listens to a child’s heart.
It seems that “mirrored” twins do happen, see here and here.
And thanks for reminding me of Sayers’ The Image in the Mirror. I’ll have to dig that up again one of these days.
I’m not a doctor but I seem to recall that the human heart is located more centrally than most people believe. See this image on wikipedia.
eta: But of course in complete situs inversus the other organs are mirrored too and that should be noticed when e.g. palpating the liver.
Sorry, on re-reading I see you know about the location of the heart. Makes mental note to use preview properly.
My Dad is situs inversus. As a kid, all the interns would parade through his hospital room, getting a firsthand view of quite a rare thing.
If you remember the real James Bond - Sean Connery - in the movie Doctor No survived an assasination because he had his heart on the other side, his organs reversed. Not common, but not unheard of.
Situs solitis - organs are arranged in the standard fashion
Situs inversus - stomach, spleen liver, the whole deal are flipped.
- situs inversus with dextrocardia Heart is also flipped.
- situs inversus with levocardia Heart stays on the left.
Kartagener Syndrome - ciliary dyskinesia, in a person with dextrocardia, they get dilated bronchi from being unable to properly clear secretions
Other partial reversals produce Asplenia (think of it as having two right sides, so mo’ liver, less spleen) and Polysplenia (mo’ spleen, less liver)
Lungs are more variable, as there are tons of normal variant lung fissures anyway. I did once see a case where the person had situs inversus and left middle lobe pneumonia. - most people don’t have left middle lobes.
Other interesting variants include 2 aortic arches, duplicated and partially duplicated kidneys, and all the myriad ways the uterus can fuse - from nothing above the cervix to 2 complete uterine cavities.
And that’s not even starting to look at the brain.
Actress Catherine OHara has this condition.
One condition this does put you at risk for is you have a higher probability of showing up in a cheesy crime drama, when you’re shot/stabbed/hacked/impaled where your heart should be and mysteriously survive.
Or a cheesy medical show.
There was a similar thread [thread=544221]here[/thread], from a couple months ago.
Americans with this condition are also prone to drive on the left side of the road. (wink)
My mother is a GPA’s assistant, and a patient told her that he “has his heart in the right place” when she prepped him for an EKG. She didn’t get it at first, but guess what 
My childhood-and-then-into-college sweetheart was a mirror twin whose sister was well documented situs inversus. Externally, the two were quite interestingly mirrored: hair sworls, moles, and other slight asymmetries very easily matchable between them. Handedness was mirrored also.
Are people with situs inversus more likely to be left-handed?
(Since if everthing is backwards, their left is like other people’s right, in a sense. Or is that separate?)