This is it, friends! 

Forget Indy and Iron Man, Hulk, X-Files and all the other big Summer movies for 2008.  The Dark Knight opens today, and is the only movie I'm getting in line for.  Growing up, I collected comic books and the dark, intense, psychically damaged alter ego of Bruce Wayne was my favorite Superhero.  He didn't have special powers (unless you consider gobs of money and a mansion to be special powers).  No, the Bat's a detective--doing CSI before there was CSI--relying on his head as much as skill. 

 Of course, like all superheroes the Batman has his Rogue's Gallergy of Villians--many of them classic pop-culture characters in their own right. 

Which got me thinking, What If (as the name of one comic book title goes), The Batman and his arch enemies inhabited our Universe instead of the DC Universe.  Would it be possible, say medically, to provide a diagnosis to explain their madness?

Let's give it a shot:

Joker 

The Bat's number one nemesis, and his most complex foe.

Symptoms (Sx):  No pigment in the skin or eyes (let's assume the hair is dyed); pure homicidal, unconscionable insanity.  In Frank Miller's groundbreaking The Dark Knight Returns, Joker walks into a TV studio and murders the entire audience--just another day in of his reign of terror. 

Diagnosis (Dx):  There's a genetic disease known as phenylketonuria (PKU) that afflicts 1 in 13,000 to 1 in 19,000 babies.  Basically, your body can't metabolize an amino acid called phenylalanine.  Phenylalanine is a building block for melanin, which gives us (drum roll please)...pigment.  Without melanin, you are pale, with blond hair and pink colored eyes.   The treatment is a diet low in phenylalanine (sorry, no Diet Coke, because NutraSweet contains phenylalanine), but left untreated the disease can lead to seizures and mental retardation.  Now what about the bad attitude? 

Now, what about the Joker's bad attitude?  Consider a phenomenon known as Phineas Gage Syndrome:  In 1848, Phineas Gage a respected and well-liked construction worker and family man was freakishly impaled by an iron rod.  The rod entered his left cheek and exited through the top of his head--like this:

 Remarkably however, Gage recovered from the injury and the ensuing infections that followed, and was able to return to work.  But it turns out he was forever a changed man--prone to random fits of anger, profanity, and irreverence.  The primary brain injury was to Gage's prefrontal cortex, which, today, is known to have a major role in our personality and behavior.  The injury altered his ability to regulate his behavior. 

So let's say that Joker, at some point having been born with PKU, had a head injury that triggered Phineas Gage like symptoms forever. 

And what about Joker's weapon of choice--a poison that causes suffocation, rigor mortis, and a gastly smile on the victim's face?  One candidate is the toxin released by the bacterium that causes tetanus, clostridium tetanii.  It causes muscle stiffening, including risus sardonicus--latin to describe the facial muscle stiffening that causes tetanus patients to look like they're smiling. 

Treatment (Rx):  A diet low in pheylalanine and tyrosine; contact lenses,; Just For Men hair dye; a rubber room

 Moving on...

Penguin

Sx:  Short stature, webbed hands (if you go with Danny DeVito's incarnation in Batman Returns). 

Dx:  Height--there are many possible reasons for his short stature but one of the most common is known as achondroplasia, affecting 1 in 25,000.  Individuals with achondroplasia grow to an average of about 4 feet.  The cause is due to a genetic mutation in a gene responsible for growth.  That gene, interestingly enough is located on the Y chromosome and is more likely to mutate with increasing paternal age.  So the older the child's dad, the more likely he or she is to be born with the disorder. 

What about the webbed hands?  Possibly due to Amniotic Band Syndrome.  In this condition, developing babies become tangled in fibers that can occur in amniotic fluid, literally creating tourniquets that can deform the body.  Cases can range in severity to relatively minor problems to stillbirths. 

Rx: Physical and occupational therapy, perhaps growth hormone therapy,perhaps limb-lengthening surgery, regular evaluations by a geneticist or orthopaedic surgeon or neurolgist, as spinal cord compression or cervical spine injuries can occur more easily in achons.  Membership in the Little People of America.

Next:

Riddler

Sx: As opposed to Joker and Penguin, Riddler has no physical pathology. No, Riddler's issues are all in his head.  The man also known as Edward Nigma commits crimes and always leaves a riddle behind for the Batman to solve as part of the game.

Dx: Obesessive Compulsive Disorder (OCD). Individuals with this condition have obessesions (thoughts) or compulsions (actions) that get in the way of having a normal life.  That's not the same as being obessive or compulsive.  All of us may pine on something or check and double check the locks on our car door.  Patents with OCD are those who do the same over and over again; they simply can't stop and they miss work or ruin relationships as a result.  For Riddler, it's his obesession with crime and his compulsion to leave a riddle as a clue and his calling card.

Rx: A really good therapist and some drugs--usually antidepressants are prescribed because they can reduce the obessive thoughts. 

 Two Face

 Sx:  Two-Face seems to have the most probable origin in The Batman's Rogue's Gallery:  Harvey Dent was the handsome, successful DA in Gotham City, until his was face was disfigured by a mobster who threw acid on it, leading him to a life of crime.  Now, Two-Face makes life and death decisions by flipping a two-headed coin--one side is clean (you live) the other side has an X inscribed over the face on it(you're dead). 

Dx:  This is a tough one, but the closest thing I can think of is Dissociative Identity Disorder, formerly known as Split Personality Disorder.  We could hypothesize that Dent, following the trauma to his face, developed dual personalities (one good/reasonable the other evil/insane) to cope with the conflict within. 

Rx: Psycholanalysis and a damn good plastic surgeon

And Finally, what of our Hero?

Sx: Vigilante who would rather spend his nights cleaning up criminal scum instead of getting a good night's sleep, running a multibillion dollar corporation, and being Gotham's most eligible bachelor.

Dx: Wayne's issues seem to fit well with post traumatic stress disorder:  his life was irrevocably altered the day he saw his parents murdered as a boy.  As an adult and even as a senior citizen (see Miller's Dark Knight again), he has nightmares about what happened, a lasting reminder of his trauma.  In addition, he chooses to isolatation over intimacy, possibly for fear of losing another close to him. 

Rx: A cowl, a bad-ass attitude, a muscle car and the first ever instant messaging system: