Julie's Website

Bethlem Myopathy--DNA and Muscles

New! PT 2011
August 2008 Bethlem Myopathy/Ullrich CMD conference notes
October 2005 Bethlem Myopathy/Ullrich MD conference notes
Update 2006
Update 2005
Update 2004
Julie's Hypotonia Story
The Medical Puzzle
The Muscle Biopsy
The Diagnosis
Physical Therapy--updated in 2008!
Seating at school
Julie's Wheels
The Sleep Studies
Julie's flexible Daddy
Bethlem Myopathy--DNA and Muscles
Julie's Bethlem Myopathy Book

How does Bethlem Myopathy make Julie different?  What things about Julie are the same?

Really, the question is how does everyone's body know how to make itself?  The answer is DNA (deoxyribonucleic acid)--DNA is the "instruction manual" for all life.  In people, DNA is over 99% the same in everyone.  It's the little differences in that 1% that make us different from each other.

Taken from: http://www.koshlandsciencemuseum.org/exhibitdna/intro02.jsp

There is a section of DNA in people with Bethlem Myopathy that tells the body to make a connective tissue called "Collagen VI" wrong.  This section is called a "gene."  Because Collagen VI is made wrong, it affects how the muscles grow and work in people with Bethlem Myopathy.  Scientists and doctors are still trying to understand just how this problem with Collagen VI affects the muscles so maybe they can find a way to treat the problem or cure it.  That's still a long way off, though.
What we do know is that the muscles of people with Bethlem Myopathy look different under the microscope.  Here is a picture of normal muscle and then a picture of muscle from a person with a myopathy (not from Julie--these pictures are from science articles). 

Taken from: http://jmg.bmjjournals.com/cgi/content/full/42/9/673

These pictures are from a person with normal muscles, a person with a more severe form of Bethlem Myopathy called Ullrich Muscular Dystrophy, and from a person with Bethlem Myopathy.  (Again, none of these pictures is from Julie, rather from a science article.)
The top two pictures are of muscle, on left, from a person with normal muscles and on the right, from a person with Ullrich Muscular Dystrophy.  You can see on the left that the muscle cells are nice and even, approximately the same size, and have lots of Collagen VI in between the muscle fibers--the Collagen VI is stained red so you can see it.  On the right, there is almost no Collagen VI and the muscle fibers are different sizes and not as nicely organized.  In a person with Bethlem Myopathy, it would look something like the one on right, but with a bit more Collagen VI in the spaces.
The bottom pictures are from skin cells and show how Collagen VI should look on the left.  The Collagen VI is stained green and looks plentiful and makes a kind of web, connecting everything together (hence the word, connective tissue).  The middle picture is from a person with Ullrich Muscular Dystrophy and you cannot see any Collagen VI.  The picture on the right is from a person with Bethlem Myopathy.  You can see some green-stained Collagen VI, but there isn't much of it and it seems like it is just hanging out there in little bunches rather than forming that nice web that it should form. 
In person with Ullrich Muscular Dystrophy, Collagen VI doesn't form at all.  The gene responsible puts a different protein in the wrong place and that screws up the formation of Collagen VI.  In a person with Bethlem Myopathy, Collagen VI does form, but not as well as it should.  The gene responsible puts a different protein in the wrong place so that some Collagen VI forms, but it doesn't look right and doesn't do its job (whatever that is!) as well as it should.
Another thing that is affected is how the muscles form:

Normal muscle--type 1fibers are tan and type 2 are brown

Myopathic muscle--many more type 1 fibers (light color) than type 2 (dark color)

Here, the type 1 and type 2 fibers are of different sizes. They should be all the same size.

The pictures above are from articles on emedicine http://www.emedicine.com/neuro/topic230.htm#target9 and
http://www.emedicine.com/pmr/topic65.htm  and show typically myopathic findings on muscle biopsies.  The top picture is of normal muscle.  There is a pretty even amount of the type 1 and type 2 muscle fibers and the fibers are pretty much the same size.  The slide below represents a finding similar to Julie's muscle biopsy--there are more type 1 fibers (light color) than type 2 fibers (dark color).  The next slide shows another finding that was similar to Julie's muscle biopsy--the size of the muscle fibers varies greatly.  Some are much smaller than the others.  They should all be close to the same size like in the top slide.

Julie and her pups, Kiwi and Cocoa

So how does Bethlem Myopathy make Julie the same as other kids and how does it make her different?
In most ways, Julie is the same.  She has fingers and toes, thoughts and feelings, likes and dislikes, and pretty much everything that any other nine year old has.  Everyone is different is some ways, like the color of their hair and which foods like they to eat.  Julie is no exception!
In a few ways, Julie is different.  Mainly, Julie is different in how her muscles work.  Because her muscles look different under the microscope, like in the pictures on this page, Julie is not as strong or as fast as other kids her age.  Her mind knows what she wants her muscles to do, but her muscles take longer to learn to do tricky things, like dribbling a basketball and running fast.
Her muscles are not as strong as other kids, either.  Most of the time they are strong enough for what Julie wants and needs to do every day, like walk around school, open and close her desk, pick up a book to read, etc.  Sometimes her muscles are not strong enough and then Julie needs help, like with opening a lid or a really heavy door.  Julie's muscles in her torso are most affected by her myopathy and that means that it can be hard for Julie to keep her balance.  This is why it is so upsetting to Julie when she gets bumped--it feels like she might fall down and that's a scary feeling.
Another way Julie is different is that she is very flexible!  Her joints can open farther and bend back farther than most people's joints can.  One joint that is not as flexible, however, is her knees.  The muscle behind her knees, called the hamstring, seems to want to tighten up and make it hard for Julie to straighten her knees all the way.  This happens to people with Bethlem Myopathy and, at times, we do stretches with Julie every night to keep her knees flexible.  So far, it's working!
Finally, Julie's muscles get tired more quickly than other kids.  It's not the same kind of tired like when you need to sleep.  It's the kind of tired that you feel when you have been running a long way and your muscles won't let you run anymore and you have to stop and walk or rest.  Because Julie's muscle are different, they have to work harder to do things and they use up Julie's energy more quickly.  This is why it's important that Julie has her chairs at school that support her body so it doesn't have to work as hard and so she won't get as tired as quickly.  This is also why it's important that Julie gets to rest her body when she needs to.
The most important way in which Julie is just like everyone else is that she has feelings.  She is not a robot!  She can feel happy, sad, mad, proud, etc.  She is a great kid and a good friend.

This page was created to explain to Julie's class about Bethlem Myopathy and how it makes Julie different.  It is not intended as medical advice and I make no promises about the accuracy of the information!  It represents my understanding and interpretation of the information and the manner in which I decided to simplify it for an audience of fourth graders.