Porphyria: A Bloodthirsty Biochemical Explanation

November 14, 2008

During one of my final biochemistry lectures I learned something very interesting and unexpected… vampires might be based on a real disease!

What?!  Why didn’t I hear about this disease before?  Well, that’s probably because people who have this genetic disease would rather not be related to vampires, who are considered evil by many. The legend of vampires exists nevertheless, and there is a real medical explanation for how it may have originated.

It makes sense that before science was able to explain strange genetic diseases and symptoms, people assumed that they were connected with an evil spirit, or a result of certain behaviors like diet.  In fact, when I lived in rural Ukraine, pregnant women refused to cut their hair or sit on anything cold, thinking these actions would cause birth defects.

Yet, now we know that genetic defects are often the result of a tiny mistake in the duplication and division of DNA.  A single rearrangement or deletion can cause a lot of strange things to happen- it’s amazing that most of us come out looking “normal.”

The possible explanation of the vampire legend is one of seven types of porphyrias, which are all diseases in the synthesis of heme (the compound in blood which carries oxygen and carbon dioxide to keep us alive).  Heme is synthesized in the liver and bone marrow.  There are eight steps, four of which take place inside mitchondria and four in the cytoplasm.  Therefore, there are multiple opportunities for defective enzymes and build-up of intermediate products.

The interesting thing about the intermediates in heme synthesis is that they contain many benzene rings.  When these rings are oxidized, they can absorb light and appear to be colored (think of purple-yellow-brown-greenish bruising when heme breaks-down under the skin).

The type of porphyria believed to have started the legend of vampires is called porphyria cutanea tarda.  It leads to a build up of products which cause a variety of problems.  First, people suffer from extreme anemia, so they are very pale.  Additionally they have red and fluorescent teeth, which can look pretty strange.

The intermediate products in their blood can oxidize to become insoluble when exposed to sunlight.  This causes pain and blistering in the skin, so those with the disease will try to avoid sunlight.  Also, drinking fresh blood, could relieve the neurological symptoms.

This type of porphyria was a genetic defect, so it stayed within families.  Since these people were probably outcasts from society, they may have married relatives causing the disease to proliferate faster.

None of this is proven fact because nobody knows where any supposed “vampires” are buried.  Otherwise, it might be possible to perform a genetic test.  Also, this explanation doesn’t explain a fear of garlic or why you have to put a stake through the heart in order to kill a vampire.

This is an extremely rare disease.  Yet, it’s interesting to begin to use modern knowledge and biochemistry to solve past medical mysteries.  I never thought biochemistry would fascinate me this much.

 


Thinking About Summer Already

November 9, 2008

Yesterday I had a phone interview to volunteer with a medical program in “campos” (villages) in rural Dominican Republic.  I want to go abroad this summer.  I hope to observe a low-cost healthcare operation and see how people are served by a service organization.  Not to mention it would be wonderful to learn some medical Spanish (a must to assist medically underserved populations in the USA).

This program sounds quite interesting, especially since I would stay with a host family and be isolated from phone or internet.  The program dates span over Ben and my first anniversary, so that would be challenging.  But I talked to Ben and he was not discouraged.  I get really excited to think about clinical experiences right now- I need to be reminded about why I am doing this.

Most of my days at school are spent looking at molecules and diagrams, and having information “poured” onto me.  Each day, I become aware of some other tiny process in the body.  Certain mysterious elements have started to become clearer.

 

I wonder what it will be like when I can look at others and myself and envision what is going on inside their bodies.  For example, right now, when I look at my torso, I can kind of imagine what things inside look like and where they go.  After a few months, I should be able to name, feel, envision, know the color and texture, and examine everything.  My torso will never be the same again after that.  Meanwhile, time is flying so fast, I can’t help thinking about summer break already.

 


Election and Health Care

November 5, 2008

This week was election week, and I’ve also been able to think a lot about that.  I skipped my classes (for the first time) to stand in line for for 1 ½ hours to vote.  It was a good experience to see so many people in line, and to spend the evening watching the results of such a historic election with our international friends.

I can’t help comparing the atmosphere with the energy in Ukraine after the Orange Revolution ended and Yushchenko became president.  Ukrainians eventually became more discouraged than ever when Yushchenko’s presidency didn’t meet their expectations.  I don’t think that the same thing will happen in the USA, but I know that Americans have difficult times ahead.

As a future doctor, I’m not sure how the political situation will affect my career.  However, I know it will, and I hope positively.  The health care system in the USA isn’t really “systematic.”   The current organization evolved without any planning.  And surprisingly, the government currently pays for over 50% of national health care costs already, and has a huge influence on the medical system.

I realize there is a I should learn about health care management and payment.   I am surprised and a bit dissapointed that nothing has been mentioned in my classes yet.  Perhaps I should be getting my Masters in Public Health too!


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