.dietzen dictionary: joubert syndrome.

Before having a child with special needs, my knowledge of medical terms, characteristics and procedures was almost non existent. I had never had surgery or even been in the hospital, so I had a lot to learn once Parker was born.

I decided that since I sometimes feel like I should have an honorary medical degree due to having to learn so much about genetics and medical conditions with the boys, that I would share what I have learned on the blog as some of you might be curious and find it interesting. Each Wednesday   I will post on a new topic, word, definition, etc. related to special needs and medical conditions that we deal with on a daily basis so you can have a general understanding of this crazy world that we live in.

I don't think I have ever done a post specifically on what Joubert Syndrome is. I know I reference a lot of the different aspects of it, but today I wanted to give an overall definition of what JS is and how our boys are affected. I am going to explain it in medical terms and then explain it how we interpret it, or explain it in the way we have come to understand it.

Joubert Syndrome (according to the website) is:

"an autosomal recessive condition, in which an affected individual has mutations in both copies of a gene, preventing the gene from working correctly. Almost always, parents of an affected individual are both unaffected carriers, because they "carry" one nonworking copy of a JS gene and one working copy of the gene. When both parents are carriers for mutations in the JS gene, there is a 1 in 4 chance with each pregnancy that the baby will be affected. It is important to note that the severity of a JS individual may be quite different between individuals, even within the same family."

Basically what this means is that Nick and I are carriers of one of the same mutated gene that causes Joubert Syndrome and our boys both got the affected mutation causing them to have two affected genes. So even though every person walking around has mutated genes in their DNA, if they have one working copy of the gene, they are not affected by the mutation. The fact that Nick and I both have the same exact mutation, then met each other, got married and had children together is extremely rare!! If you remember back to biology class, it is like the figure below for the genetics. Each pregnancy has a 1/4 chance to be totally unaffected and not a carrier; a 2/4 chance of being unaffected but a carrier; and a 1/4 chance of being affected as well as a carrier. 

(B=unaffected gene; b=affected gene)

It's also interesting that they make note that the severity can vary within the same family, even though they would be affected by the same gene. This was part of the reason why we could not tell immediately whether Lane was affected or not. Parker seems to be more severely affected than Lane, and struggles a bit more, especially with the fine and gross motor skills. Lane is two years younger than Parker but can do certain physical things better and more coordinated than Parker and has hit his physical milestones much quicker than Parker did.

Joubert Syndrome is characterized by:

the absense or underdevelopment of the cerebellar vermis (an area of the brain that controls balance and coordination) as well as a malformed brain stem. The most common features of JS include abnormally rapid breathing (hypernea), decreased muscle tone (hypotonia), abnormal eye movements, cognitive impairment, and the inability to coordinate voluntary muscle movements (ataxia). Physical deformities may be present, such as extra fingers and toes, cleft lip or palate, and tongue abnormalities. Kidney and liver abnormalities can develop, retina deterioration and seizures may also occur. 

When we first went to the neurologist with Parker when we first had our concerns, he noticed three things that led him to believe Parker had a brain malformation of some sort. He noticed the abnormal eye movements, the low muscle tone (hypotonia), and his inability to coordinate movements. Because of these three markers, he scheduled the MRI to get a clear image of his brain and get a diagnosis. Because of the lack of development of the cerebellum and the malformed brain stem, when looked at on an MRI, it looks like a molar tooth (see image on right). If you were looking at a typically developing brain, there would not be the molar tooth (see image on left). The image on the right is almost exactly what both Lane and Parker's MRI looked like. Pretty interesting to see their brains and see exactly where the malformation is.

(Image from UW)

After Lane's MRI

While the boys are affected by most of the things that characterize JS, not all apply to them. Both Parker and Lane have abnormal eye movement (Parker much more so), low muscle tone (the reason why they are delayed in crawling and walking), and have trouble with balance and coordination (ataxia). We are fortunate that they do not have rapid breathing issues, physical deformities, and so far have not shown any signs of organ or eye involvement. Another huge blessing is that the boys have very mild cognitive impairment. While they have been delayed in talking, they are very smart boys and have tested within the normal range for age appropriate cognition/intelligence.

Yearly ultrasound for kidney and liver

Yearly ultrasound for kidney and liver

Treatment and Prognosis:

While there is not "cure" or way to prevent or treat JS, there are many things that we do to help combat their struggles and give them a chance at a bright future. Treatment is symptomatic and supportive-meaning as issues arise they are addressed and therapies and things are done to support and help progress the individuals.

Our boys are currently in physical therapy, occupational therapy, speech therapy, feeding therapy (Lane), horse therapy (Parker), and special services preschool (Parker). We also have a nephrologist (kidney specialist), ophthalmologist (eye doctor), neurologist (brain doctor), hindbrain malformation team (University of Washington), Early Intervention coordinator, Special Services coordinator and pediatrician that we meet with on a yearly basis. Seeing these specialist helps us to monitor their development and any potential issues that could occur at any time.

Foot orthotics for support while weight bearing

Yearly eye exam to monitor retinas

Yearly eye exam to monitor retinas

The prognosis for the future is hard to define because there are so many factors that play into it. Because the boys biggest challenge is their muscle tone and not necessarily their mental development, their futures seem to be pretty hopeful. Since JS is not a progressive disorder/disease, once they gain a skill, they will not lose it and will only continue to develop that. For example, once they start walking they will only get stronger and build upon that. So we are hopeful that they will not be limited by their physical disabilities that we experience now. There will be things that need to be modified but they have the mental ability to achieve a lot and we believe that they will be able to live independently someday.

Our Perspective:

Because of the rarity of Joubert Syndrome and the chances of Nick and I both being carriers, we truly believe that we were chosen to be Parker and Lane's parents. Sure there is all the science and genetics involved in it, but we believe God knew what he was doing when he put Nick and I together. We have a huge opportunity to help people understand the special needs community as well as how to deal with and walk through unexpected circumstances. The struggles and abilities that the boys struggle with seem huge and daunting at times, but things could always be worse and we are thankful for how much progress they have made so far. I am always learning something new and it has given me a passion to purse nursing or pediatric therapy as a second career in the future. 

Some reference sites for more information:

http://jsrdf.org/

http://www.ninds.nih.gov/disorders/joubert/joubert.htm

http://depts.washington.edu/joubert/joubertsyndrome.php

If you ever have any questions or things you are curious about hearing and learning about, just leave a comment and I would love to address it in the future!!