Friends With FOP

Posted by Karen

A couple of days ago I found out Miranda has her first loose tooth!  I was a bit surprised, as she’s only 5 years and 3 months old.  That’s at least a year younger than her brother was at the same stage.  Anyway, having the first tooth fall out is a big deal…  *Sniff * – where did my baby go?

The loose one is one the bottom row, just to the right of the centre of her mouth.

Miranda doesn’t attach much significance to this event – she’s just excited about an impending visit from the tooth fairy.   Those baby teeth are, however, important in the world of Fibrodysplasia Ossificans Progressiva research. 

Think about it…  If you’re a scientist and you want to study a disease process, what’s one of the first things you’d do?  The answer is that you’d probably take a biopsy, so you could look at the affected tissue under a microscope.  This is, generally, a time-honoured way of starting to figure out a disease.  However – biopsies are a very bad idea for people with FOP.  Why are biopsies problematic, you may ask, and what does that have to do with baby teeth?  Well, aren’t you lucky (ha ha), I’m going to tell you…

The thing with FOP is that traumatic events can, and often do, cause the excess bone formation characteristic of FOP.  If a person with FOP suffers trauma to muscles, tendons or ligaments, that will often be a triggering event which causes a “flare-up” and eventual new bone.  Sometimes the impact to the tissue doesn’t even have to be severe – a fall on the floor, for instance, could do it.  Accordingly, if a doctor does a biopsy – ie, cuts open the person’s flesh and removes a piece of tissue – that’s a traumatic event with excellent potential to lead to explosive new bone formation (“explosive” – that’s the term often used by our own UPenn experts). 

As you can see, it’s not a good idea to do a biopsy on someone with FOP.  Because of this, biopsied samples of human tissue affected by FOP tend to be rare, and usually only taken in instances where the FOP was undiagnosed at the time.  That, incidentally, can be disastrous.  A child has a strange swelling that no-one can identify, so a biopsy is done.  The process of taking the biopsy makes the site of the swelling more “angry”, and causes the swelling and eventual bone formation to spread much further than it was going to in the first place…   (*shiver*)

A scientist obviously doesn’t want to do more harm to a patient, so biopsies are not indicated for people with FOP.  But…  How then can researchers study what changes FOP makes at the microscopic level?  For quite a while, this was a major hindrance to FOP research.  Scientists tried taking only skin or blood samples from people with FOP (those procedures don’t lead to flare-ups if done properly), but they found out that skin and blood tissue don’t react in the characteristic FOP ways.  It turns out that to look at, or do experiments on, tissue with FOP qualities, you really need stuff from the kind of biopsies you can’t do.

This is where the teeth come in.  As it happens, baby teeth which fall out have, for about a day or so, a few small shreds of living gum tissue still attached.  At some point along the line, FOP researchers got the brilliant idea of trying to harvest those small mushy bits from the teeth and checking to see if THOSE cells would show signs of FOP.  Bingo!  It worked.  It turns out that the flesh of the gums, as found in lost baby teeth, can be effectively used for FOP research purposes.  Those amounts of gum are small, but are enough for researchers to develop new lines of cells for study purposes.  I understand this has been extremely helpful for scientists in trying to understand how the disease works and doing cellular level experiments.

The scientists spread the word in the FOP community, and they developed a protocol for retrieving the valuable gum tissue as quickly as possible after a tooth falls out.  Obviously, time is of the essence – if one waits too long, the living cells die and become much less useful.  The process of getting these all-important teeth to the FOP lab at UPenn has become known as ”the Tooth Ferry” (great pun; I love that).

Miranda’s tooth hasn’t fallen out yet.  In fact, it’s only just slightly loose, so I figure it’ll be another two or three weeks before it falls out.  However, you can be sure that when that exciting event happens, we’ll be putting that little gem on the Tooth Ferry – destination: UPenn.

The only problem here is that Miranda won’t have a tooth for the tooth fairy.  However, I’m sure she (the fairy) will understand.  When Miranda’s brother Owen had a tooth fall out and get lost at daycare, we left the fairy an explanatory note, and that worked just fine.  I’m sure that will do in this circumstance as well. 

Miranda herself dressed as a fairy, circa Halloween 2008.