About this blog

I am a high school human anatomy and physiology teacher by trade and I double as a mother of a little girl with Williams Syndrome. When my daughter was diagnosed, I was thankful that I understood how the body worked so I could navigate through the condition and understand what the doctors had to say. This is my way of sharing my knowledge so other parents can have that same power.

Information contained in this site is strictly for education purpose to better understand the conditions associated with Williams Syndrome. You should in no way use this site for diagnosis, treatment or medical guidance. Always seek medical advice from your doctor.

Saturday, August 9, 2014

Back to School Tips for Teachers

Just this week I walked my daughter into her Kindergarten classroom to meet her new teacher.  This time of year brings me joy mixed with fear... definitely bittersweet.  I know Katie will thrive in her new school with her new team of teachers, therapists and aides, but part of me always worries about her.  I'm sure you can relate.  So, I challenge you to ask yourself- what can you do about that?  I hope your answer is the same as mine...I advocate for her.

In my own classroom I typically have 20+ students with IEPs and among them I've had very few parents reach out to me before the beginning of the school year.  But when they do, I immediately have an elevated level of respect and ambition to go out of my way to help them achieve their goals and needs!  Normally at the start of a new school year, it takes me time to get to know my students and identify their needs.  It takes me even longer to find the best solution to meet their needs.  Why not, as a parent who knows what our children need, help accelerate that by reaching out to teachers and giving them a toolkit of research based accommodations specific to your child?  By contacting your child's teacher you can share those resources so they can start the year with strategies and plans to help your child succeed from day one.  So, in this post, I'm sharing my WS toolkit with you.

In addition to the toolkit, I gave my daughter's teacher the bio I made called "All about Katie".  I used the bio last spring at her annual IEP.  It includes her picture, nickname, strengths, weaknesses, concerns and family goals.  I think that we often share these at IEP meetings but forget regular ed. teachers often don't get to see those.  They usually only receive a copy of the legal IEP at the beginning of the school year. 

A simple email establishing positive communication with your child's teachers will create a smoother transition to their new classroom.  Approach your new teacher with an open mind and be cognizant that they are extremely busy and stressed this time of year.  When I sent these materials I was mindful of how I worded my email to show that I respected their time and dedication to their students.  I kept it short explaining that I wanted to help them by providing resources that could act as an easy guide to help them solve problems that may come up as they get to know Katie and her needs.  They can also use them as a way to be proactive in her learning.  For example, it makes a teacher's job easier if they know if a child needs preferential seating or an audio book in advance so it can be available on day one.  Plus, opening up that communication breaks the ice and shows them that you have high expectations but that you are also part of the team and want to work with them in a collaborative fashion.

Below you will find my newest infographics that go along with topics I presented at the convention on visual-spatial issues followed by a collection of educational strategies that I learned about this summer.  Also I included a quick chart showing common behavioral challenges and social strategies that are common in children with WS. Following the infographic, you can find links to my other infographics and blog posts that are education centered and WSA resources that would benefit both a regular education and special education teacher.

I wish you and your children the best of luck in the new school year!  

Links to other infographics and resources I shared with my child's new classroom teachers:

If you find any of these infographics difficult to print, feel free to email me at mooniersarah@yahoo.com and I'll send you a pdf version.

Sunday, July 20, 2014

2014 WSA Convention Questions Answered Part 2- Radial-ulnar synostosis

This is the second of my series of blog posts in response to questions presented to me at the 2014 Williams Syndrome Association National Convention.  See Q1 here.

Q2:  Is Radio-ulnar synostosis related to WS?

 One of the clinical symptoms related to WS is radio-ulnar synostosis or an issue where the radius and ulna are fused in a person's lower arm(s).  A typical forearm is designed in a way to allow the hand to maneuver in a variety of ways in order to manipulate objects in the hand.  When you extend your arm out with the palm facing downward (pronation) and then twist your palm to face upwards (supination), the bones in the lower arm direct that motion. 

In the pictures above, the radius is highlighted on the left drawing and the ulna is highlighted in the right drawing.

The lower arm is made up of two bones, the ulna and the radius.  The ulna is the bone that makes up the elbow.  Touch your elbow, you are touching a large protrusion on the superior portion of the ulna,  called the trochlea.  The ulna also articulates or creates a joint at the outer most edge of the wrist but in a much less pronounced way.  The second bone of the lower arm is the radius.  The radius articulates or connects to the majority of the bones in the wrist and extends to the elbow where it ends with a small concave circular notch that allows it to turn.  The radius is named for this motion.  Place your hand on your ulna (elbow) and follow that bone down the outside of your arm.  Now twist your palm up and down and notice that bone moves very little.  The other bone, the radius, moves quite a lot!  The radius is on the inside of the arm and it rotates around the ulna.  Watch this short youtube video to see an "insider's" view of how these bones twist the hand.

Now, imagine the radius and ulna bones are connected.  Would you still be able to twist your palm up and down?  No!  This is what happens during radial-ulnar synostosis or the fusion of the radius and ulna.  It affects 26% of individuals with WS.  My daughter has this in her right arm and it restricts the amount of motion and actions she can do with her right hand. 

 In the photos above, the left is an x-ray view of a typical bone arrangement in the elbow.  This is in supination position (palm rotated upwards).  The photo on the right is one of an individual with radial-ulnar synostosis.  Their radius and ulna are fused at the elbow making it impossible for them to rotate their lower arm.
 If your child has radial-ulnar synostosis, there isn't much you can do, medically, to treat it.  Even if the bones were surgically separated, they will not have the same bone structure, vascular supply and ligament/muscle attachment that would allow the bones to rotate properly.  You would be hard pressed to find a surgeon to do this type of treatment unless the fusion very severely limits any use of the arm.

The best way to handle this condition is to modify surroundings and teach the affected individual adaptations they can use to manipulate objects.  You may often find that they have a harder time manipulating small objects and holding writing utensils, such as pencils and crayons.  My daughter shows preference in her left hand for writing but that wasn't always the case.  She often manipulates items with her right and then will switch to the left.  This may be her way of adapting to her environment since she has more movement in the left than her fused right arm.  Many find that being ambidextrous out of necessity is the case for those with radial-ulnar synostosis.  Other actions that may be difficult if they have a  fused arm includes:
  • holding spoons/forks during feeding
  • manipulating buttons, belts and zippers
  • sports that require wrist rotation such as catching a ball
  • turning a doorknob
  • handwriting
  • manipulating coins and other small objects
  • pouring liquids
  • playing instruments such as guitar that requires wrist manipulation
This website has some very interesting stories about the challenges and accommodations that come with this condition in the comments section.  The commenters are individuals who have lived with radioulnar synostosis.  *Note, this condition exists outside the world of WS so please don't assume the commentators have Williams syndrome.  Check it out here.

Coupled with the visuospatial issues and motor control that individuals with WS have, the tasks listed above can be even more difficult. You will find that if your child has radioulnar synostosis, they will adapt on their own but there are many ways you can help.  For example, you can chose clothing that doesn't require buttons or replace knobs on doors with handles.  There are also many adaptive technology apps that are available to help your child with academics and self help skills.   This was a major topic of interest at the convention.  To access the WSA's list of useful apps visit the website here.  

If you have specific ways you have helped your loved one or students adapt to radioulnar synostosis, I'd love for you to share.  Please feel free to leave your experiences with this in the comments section of the blog or on the WS support group thread!

Radio- ulnar synostosis and its occurance in WS; 1991 *Note this was published prior to the use of FISH testing for WS diagnosis so information is clinical.

Thursday, July 17, 2014

2014 WSA National Convention Questions Answered Part 1- Inheritance

Just one week ago, we completed the Williams Syndrome Association's National convention.  The experience was very different for me in comparison to my first convention in 2010.  At the 2010 convention my daughter was newly diagnosed, I was an overwhelmed and scared parent.  Fast forward to last week and I was in company with the experts, presenting and answering questions.  It was extremely humbling, overall heartwarming and one of the most rewarding experiences of my life.  This blog was just a little idea I had that spawned from learning about WS in my daughter's first year.  I'm eternally grateful to the world of social networking, Internet and supportive organizations like the WSA to literally change my life and others by increasing awareness and education to the parents and community.

During the convention, I spoke about sensory motor pathways and the genetics of WS.  I plan to have a few new posts that share the information I presented at the convention in the near future.  Look for those and others that have been requested (such as urinary and kidney issues in WS and sleep).

I was busy keeping notes of questions that ventured my way throughout the week.  Since many questions we have are on other's minds, I thought I'd answer them in a series of blog posts.  I'll post info as I learn them :) 

Q1:  Is the likelihood of a WS parent having a child without WS really 50%?

This question came up during the genetics session.  The reason behind this is that some families are skeptical that there really is a 50% chance of their child with WS eventually having a typical offspring.  We rarely hear of WS adults with children and those we do hear of often have children with WS.  While I don't know of nor have actual records of parents who have Williams syndrome and have typical children, all the literature says that the likelihood is 50%.

This is because of the process of meiosis.  When a person creates eggs or sperm their cells go through a process called meiosis where they duplicate their chromosomes, shuffle the genes during crossing over and then distribute them into two groups and divide.  In the second half of this process, they divide again to create two unique cells.  The result is four unique gametes each containing half of the parent's chromosomes.

So, if a person with WS divides their chromosomes in half, one half of them will contain the deleted portion and one half would contain the full genetic sequence.  From this point, we call the 50% the probability of inheritance but in reality, it's all chance.  If you flip a coin a couple of times is it likely you'll get heads both times?  Yes!  So it's fair to say that a person with WS could potentially have children who all have WS.  Now consider the full genetic potential of one person.  In her lifetime, one female creates upwards of 6 million eggs before she is born and a male can produce nearly 525 billion sperm!  So if you flip a coin 6 million or 525 billion times guess what the likelihood of getting heads?  50%.  That explains why you might see families with parents who have WS and their children all have WS.  It's the game of statistics.

I'm unaware of studies that are following data on this topic but with the improvement of the WS registry and parents asking for this information I could see this information being available in the future.

Learn more about inheritance and the basics of genetics and WS here.

If you have never experienced a National convention for WS, I highly recommend you try for the Ohio convention in 2016.  I found many outlets for financial support and made the trip affordable for my family.  The wealth of information you gain and the networking you can participate in is worth every cent.  In the meantime, check out www.williams-syndrome.org to find audio recordings of the convention sessions for sale.

Future blog topic requests that came my way during the convention:
Urinary and kidney issues in WS
Improve the gene list and functions
Anxiety, obsessions and meltdowns 
Causes of sleep issues in WS
Teaching social skills and friendly conversation

Have any other requests or more info on this blog post?  Leave a comment.  I'd love to have powerful dialog occur on these posts from parents like you.  Stay tuned for more Convention Questions Answered within the next few days!

See the answer to question 2:  radioulnar synostosis here.

Wednesday, March 19, 2014

Teaching Strategies Guide for Educators

Spring marks the beginning of many annual IEP meetings including my own Katie's transition to Kindergarten!  This time of year can be stressful for many families, so to prepare, I've created an infographic you can print out and share with your IEP team to help identify research-based best practices and appropriate accommodations for kids with WS.  Feel free to download or save this and print as many as you'd like.  I hope it can help facilitate positive conversations about your child's needs... and remember, every child is an individual so some of these strategies will be effective and others will not.  You, as the parent, know your child the best so be an advocate and vocalize what you know works!  All the information on the infographic is compiled from the educator guides at www.williams-syndrome.org.  Best of luck!

Tuesday, February 18, 2014

Understanding Elastin

Elastin.  It's a term many families affected by WS recognize immediately, yet in regards to what it really is, many may not fully understand.  Elastin is a famous term used in the WS world because it is used to obtain a diagnosis using a FISH test.  So what is elastin and how does it cause some of the more famous symptoms of WS?  In this blog post- and on my webcast through the Williams Syndrome Association- we'll explore the ELN gene, how it is used by the body and its role in many WS symptoms.  This blog post will give you an overall idea of its role and links to posts on symptoms affected by the absence of ELN.  The webcast has more details and a Q&A at the end that you may be interested in.

So what is ELN?

ELN is one of the genes affected by the microdeletion on chromosome 7 that causes WS.   I often hear many refer to it as a chromosomal deletion which is not the case at all.  In fact, it's a gene deletion called a microdeletion because very few genes are missing- only about 25 on average.  Your body has 46 different chromosomes.  23 came from your mother and 23 came from your father.  Together, they make you a whole person.  Inside those chromosomes sit a series of genes that code for various proteins.  On chromosome 7, the one affected in WS, there sits between 1,000-1,300 genes.  If you had a chromosomal deletion, you'd be missing all 1,000+ because one entire chromosome would be missing.  WS, in contrast is missing roughly 25 genes that sit on one of the lower arms of the chromosome.  This is called a microdeletion.  It's just a small section of the gene sequence was left behind during a phase of meiosis when the body jumbles the genes to create diverse offspring.  (See the genetics page of this blog for more info on crossing over).

Out of those 25 genes, one of them is called ELN.  ELN is deleted in such a high majority of WS individuals, it creates a very reliable gene to "look for" in genetic testing.  Before we knew so much about ELN, we focused most of our research about WS on symptoms such as narrow arteries.  The presence of narrow arteries is the number one reason individuals with WS have life-threatening issues.  Because of this, it is considered a high priority area to study in the WS research world.  At the time, they took a backwards approach to genetics.  Researchers would study the disorder, identify how the tissues were arranged or functioned differently and then tried to pinpoint the protein that caused that change.  From there they would look for the gene that coded for that protein.  In SVAS, they determined that gene was ELN.   Now that we know the region where the genes are missing, we can use a much more efficient molecular genetics to identify proteins and explore WS.  The discovery of ELN not only helped better diagnose the disorder, it opened many doors in genetic research to better understand that portion of the genome.

Genetic testing used to diagnose WS is a relatively "new" method.  Prior to this diagnostic test WS facial characteristics and common symptoms had to be recognized by a medical doctor.  In the 1990's the FISH test (Fluorescence in situ hybridization) for ELN was created.  The use of this diagnostic tool increased the means to diagnose and better understand WS.  (learn more about FISH testing here).   As our knowledge of the genetic world increases, we learn more and more about ELN, increase information available to doctors and families by new diagnostic testing, such as in microarrays and increase the potential to lessen the effects of the missing genes using gene therapy.

How does the absence of ELN become a problem such as a heart defect?

Your chromosomes are made up of so many genes, each like a book in a library or a chapter in an instruction manual.  Each gene codes for a specific protein.  Proteins are the workers of your body.  Their functions span many areas such as building materials, enzymes that make important reactions happen, tunnels that transport materials across membranes, even tubes that transport materials around the cell.  Some of your genes are only active during specific events in your life such as embryonic development or puberty and others are active all the time- maintaining cell structures or aiding in reactions that help you digest food. 

ELN is the type of gene that is expressed or "read" during fetal development and during the first few years of life and then continually through adolescence until your body completes its growth.  After puberty, the ELN gene essentially sits dormant for the remainder of your life.  Because of its relatively long lifespan- lasting up to 70 years, the body's need for making new elastin decreases greatly as we age. 

When geneticists talk about a gene being expressed, they are referring to the process that occurs in the cell where the DNA is transcribed to RNA and RNA is used to create a protein.  During fetal development, the baby's body is building many new structures.  The organs in your body are made up of many different combinations of materials and tissues.  The gene sequences such as ELN are very active during this stage of life in order to build functional organs and structures.  It all starts inside the nucleus during transcription.  The section of chromosome 7 that contains ELN unwinds.  An enzyme named RNA polymerase unzips the section of DNA and matches the base pairs with RNA bases, essentially copying it.  When it reaches the end of the segment, the new RNA strand (called messenger RNA or mRNA) leaves the nucleus to deliver the sequence to the protein maker- the ribosome. 

When it reaches the ribosome, the mRNA feeds through this structure and is translated.  During translation, the ribosome matches codons- or groups of 3 base pairs to an anticodon on a transfer RNA.  The transfer RNA are aptly called this because they transfer the amino acid or protein building block to the ribosome.  This match allows the cell to build or connect each amino acid into a strand in the proper order needed to make the desired protein. 

When ELN is translated, it creates the protein called tropoelastin.  When translation finishes the assembly of the amino acid strand the endoplasmic reticulum or ER takes the protein and coaxes it into a properly folded formation.  Protein amino acids vary in their chemical composition.  Many of them have polar or charged portions that attract to oppositely charge areas on other amino acids.  This allows the protein to fold twist and connect to areas creating a unique shape.  This shape is very functional.  It gives the protein functional active sites that are designed to attract or repel molecules and "make things happen" within the cell. 

The shape of tropoelastin is that of three parts or regions.  The head of the molecule (labeled NC in the figure) is the portion that gives elastin its spring.  It can stretch up to 8 times its relaxed state and then spring right back to its original structure unharmed.  This becomes very important to its function in the tissues, which we'll get to in a bit.  The second region just under the head is called the bridge.  The bridge is an area that acts like a shock absorber.  It absorbs energy from the coiled portion in order to prevent its base from becoming dislodged.  The base functions to connect tropoelastin to an area of the tissue called the extracellular matrix.  It is essentially an anchor to hold the tropoelastin in place. 

So, is tropoelastin the same as elastin? 

No!  Tropoelastin is the main building block to a fiber called elastin.  Once tropoelastin is created and packaged into its unique shape by the ER, it then is used as a building material to make elastin.  Elastin is a fiber made of tropoelastin, microfibrils and is assembled by a group of five enzymes- called lysyl oxidases.  As tropoelastin is created, it is shipped an area outside of the cell membrane where they accumulate.  As they accumulate, one of the enzymes facilitates a chemical reaction on the tropoelastin to create cross-links or areas where they can soon connect.  Essentially, it's like nailing brackets onto the structural material so you can connect them into a sheet.   The cross-linked tropoelastin are then attached and woven to a series of microfibrils or tiny protein fibers that make up the extracellular matrix of connective tissue.  This is basically a net that creates the foundation of a tissue and contains fibers, cells and is surrounded by nutrient rich fluids.  The result is the fiber elastin.

So, in an individual with WS, this assembly line of elastin production has a decrease output because one set of the ELN is absent.  ELN is still transcribed and tropoelastin is still assembled but only in half the output as a typical person.  Think about a factory that assembles a product.  If you cut your workforce and materials by half, you'll only get half the product.  That is what occurs in WS.  They still make the tissues and build the organs but because less tropoelastin accumulates outside the cell, the resulting elastin fibers are smaller and less springy.

How does this cause symptoms of WS?

Elastin is a major component of many connective tissues.  There are several different types of connective tissue that have many different functions- the most important being support.  Most connective tissue acts to do just that- connect organs in the body.  They, for example, provide a net of support for epithelial (skin) layers in the body, they connect muscle to various organs to provide that organ movement.  They might connect vessels and fat to the organ to provide important nutrients.  They can store water, fat and salts needed for the organ's function.  They also provide support to maintain the organ's shape- a key function of elastin. 

Within all connective tissue are many different structures- there are the cells, often called fibroblasts which make the fibers, like tropoelastin.  There are fibers such as elastin and collagen that provide elastic properties or collagen which is strong and structural.  There are several proteins such as microfibrils that provide a framework or net and the extracellular matrix is often filled with fluids.  So, as you can see, the structure of an organ often requires elastin as a major structural component needed for the connective tissue to function properly. 

Elastin is essentially needed in any organ that requires some sort of stretch in order to work properly.  These organs include the heart and vessels, the skin, the lungs, and the joints.  As those organs stretch or widen, elastin stretches, (much like a rubber band but so much better!) and then springs back to an unaffected relaxed state.  This molecule is so good at this stretching job that most people's elastin can function properly for 70 plus years... pretty amazing material! 

Much of the symptoms related to elastin have been discussed elsewhere in this blog.  Below is some additional information about the disorders related to elastin and then you'll find a link to the blog page that gives more information. 

Elastin and Arteries

Until the early 1990's, little was known about the link between elastin and one of the most common vessel issues in WS- Supra-valvular aortic stenosis (SVAS) refers to the narrowing of the major vessel that leaves the heart- the aorta.  The narrowing occurs just above a valve or doorway that prevents the blood from falling backwards into the heart.  Typically in WS there can be overall narrowing in all the major arteries of the body- four of primary concern are the aorta, pulmonary arteries (going to the lungs), the coronaries (delivering blood directly to the heart tissue) and renal arteries (those that deliver blood to the kidneys). 

When the body builds an artery, it assembles the structure using four main tissues- inside, the endothelial layer is built of epithelial tissue.  This is like a skin-like lining that comes into contact with the blood.  Outside the inner layer is the media tunic.  This is composed of connective tissue and smooth muscle.  In a typical artery, the media layer is made up of very organized parallel bundles of smooth tissue and elastin.  This layer functions to control the size of the artery and regulate blood pressure.  In WS, the elastin, like discussed early, is much smaller in size due to the lack of tropoelastin present in the tissue.  Studies of the media tissue layer suggest that the pattern of elastin and smooth muscle becomes very disorganized and due to the lack of elastin, excess smooth muscle is layed down in an effort to compensate causing the vessel to loose it's stretchy quality and a much narrower formation is created. 
Diagram shows WS elastin on the left (notice the lack of tropoelastin) and a typical elastin on the right.

Considering that SVAS is the most life-threatening condition for those with WS, there is a large amount of research being conducted to better understand the mechanism or ways the vessel becomes narrow.  Unlike pulmonary stenosis, SVAS can worsen as a person ages.  As scientists isolate exactly how this occurs, there is hope that they can develop medications that might decrease the inflammation and decrease the degradation of elastin to control the worsening of the disorder.

Learn more about SVAS and it's affect on the body on the cardiovascular page of this blog.

ELN and its task force

While scientists have identified that the lack of one ELN gene is the cause of SVAS, they are suspect that ELN in combination with other genes that regulate its expression are involved in many other symptoms of WS including soft skin, premature aging, and facial features such as puffiness above the eyes.  Studies of ELN began with SVAS because it was so prevalent in individuals with WS.  As many parents are aware, WS has a spectrum of symptoms.  Even though 99% of individuals are missing one ELN then why doesn't everyone have the same symptoms at the same level of severity?  The answer is in the enzymes.  The expression of a gene takes an entire task force to copy the gene, create the protein, organize the protein, and build it into its final structure.  Even then when the fiber is damaged, there is a task force to either repair or replace it.  This is all orchestrated by proteins and that is probably where the spectrum effect lies.

Scientists have been busy at work trying to identify the genes and enzymes that have a hand in causing the more severe cases of WS.  As the amount of research improves and these genes and enzymes are identified, we may find better ways of predicting issues and treating them. 

For a great example of this, visit the section on scoliosis in this blog.

ELN and the skin

Elastin is an important component of the skin.  It's found in a layer called the dermis which sits under a thin protective layer called the epidermis.  The dermis has many different functions and is the working portion of the skin.  In the layer closest to the epidermis is called areolar tissue.  It's loosely woven with collagen (for strength), elastin (for stretch), cells called fibroblasts (for building more fibers), and a salty water environment.  You use this portion to store water and salts and create sweat.  It has many blood vessels, nerves and hair follicles that live here, too.  Under the areolar tissue is a layer called dense irregular.  This is densely packed with collagen and elastin fibers in bundles that twist and turn in many different directions. 

This is the portion that creates structure to your skin.  Imagine a pregnant belly.  As it grows and grows the skin must stretch and adapt.  Then after pregnancy it (ideally!) returns back to normal.  Now I can't speak from experience with this (ha ha) but if you can maintain the integrity of the elastin and collagen fibers, the tissue can remain in tact.  If you can't, there are enzymes that gobble up the damaged skin and quickly lay down a repaired section- leaving you with stretch marks (which is essentially scar tissue). 

Now, your probably thinking "how does this all have to do with WS?"  I use the pregnancy example because its easy to visualize the damage that can occur.  Damage also occurs with everyday life.  Aging is definitely something that everyone has to deal with.  Overtime, the lifespan of elastin can break down and lose its integrity.  As we become exposed to sun, smoke and other carcinogens the damage can accelerate.  Individuals with WS tend to have early onset of aging and it all has to do with damaged elastin.  As damaged elastin is discovered, the body disassembles it with an enzyme called elastase. You also have another enzyme called alpha 1 antitrypsin (AAT) that slows down or inhibits elastase.  It's basically a control so the enzyme doesn't go crazy and gobble up all the elastin in site.  Scientists have been studying AAT trying to identify its role in WS.  There is some evidence that some variations of AAT may contribute to more severe issues related to elastin.  There are still many questions unanswered but many clues to the complicated role to how genes and proteins influence one another.

So, in conclusion, everyone has a degree of elastin damage as we age.  In WS, where they are beginning with less elastin present in the dermis, the aging process will become more transparent over time. 

ELN and the vocal cords

Another area of the body that is affected by missing elastin is the vocal cords.  Almost universally those with WS have a hoarse voice.  The root of this lies in the flexibility of the vocal cords.  Vocal cords sit in the larynx or voice box of the wind pipe.  Men with prominent Adams apples make it easy to identify the location.  The Adams apple or larynx is composed of tough cartilage that creates a somewhat stiff box.  The cartilage is supported by many muscles and ligaments that attach to a bone called the hyoid. 

As we speak, we manipulate the pressure within the larynx which moves and vibrates a portion called the vocal folds.  The histology or layers within the vocal folds are mainly made of elastin. There is one jelly-like layer that is primarily elastic and another layer called the lamina propria that is thicker with elastin. This provides the flexibility of the folds to move with the pressure difference of the larynx during speech.  Another, leaf shaped flap called the epiglottis sits over the vocal folds. This flap is responsible for closing off the windpipe when you swallow food. It can also vibrate as well, contributing to the sound of your voice.  The vocal folds are primarily composed of elastin layers so in WS they do not vibrate and move as easily causing a hoarse tone of sound. 

ELN and the digestive system

The last place in the body that is most affected by the absence of elastin is the digestive system.  The abdomen is a relatively open area, not containing any bones to shelter the organs.  Because of this it relies on a combination of muscle and connective tissue for support.  There is a layer of integument or skin that creates the internal lining of the abdomen, called the peritoneum.  The peritoneum, like the skin, has a layer composed of elastin netting that allows it to stretch.  This lining is important in pulling in the abdomen and supporting the core. 

When elastin is weak here there, the internal organs, mainly the intestines, can bulge through the netting and get caught up in the abdominal wall.  This is called a hernia and can be pretty common in WS.  The problem with hernias is that they can be uncomfortable but they can also get infected if feces or bacteria get stuck in them.  This can cause inflammation.  Hernias are typically noticeable on the outside of the skin because a pocket or bulge will form under the skin.  Hernias need to be repaired surgically.

The most common type of hernia is the inguinal hernia.  This occurs during infancy and is most common in males but can still occur in females.  In males, as the reproductive system develops, there is a canal, called the inguinal canal, that the testes descend or move down through.  This canal then closes up, typically.  In inguinal hernias the intestines slip down through the canal as well and a hernia develops in the groin.  This can be attributed to missing elastin because the wall of the abdomen and the canal itself is looser than typical.

Another issue that can occur as people age is diverticulitis.  This is similar to hernias but instead of the intestine getting caught in weak spots of the abdominal wall, weak spots on the intestine, itself create loose pockets.  This too can get infected.  This disorder is usually found in the elderly population but because of the nature of the elastin in WS, it can happen much sooner.  There are records of people as young as 17 who have developed diverticulitis in the WS population. 

ELN in the joints

The final area of the body that is affected by elastin is the joints.  Most notably the intervertebral discs of the spine.  I have a lengthy post on posture that discusses this topic.  Go here for more info.

In sum...

As you can see, not all symptoms or complications of WS are attributed to ELN but its discovery was infinitely important in today's understanding of WS.  It opened doors in genetics to help diagnose and better understand the region where WS occurs.  It opened doors in cardiology to help understand and treat the #1 cause of fatal complications.  It's discovery has completely changed the care and open avenues for research in the WS world.


Saturday, February 15, 2014

Webcast- Understanding Elastin

I'm excited to announce that I'll be hosting a webcast for the Williams syndrome Association on Tuesday February 18th and 7 p.m. central time.  Join me by clicking here and registering!  The webcast will be archived on the same webpage after it airs so if you miss it, you can hear it at anytime.