The Wonderful World of Neuroscience: Juvenile Huntington Disease

         Hello Folks! Welcome back to another science article to brighten your minds! Today, we get to discuss a topic that has long interested me, despite my initial reluctance to delve into it: neuroscience. More specifically the disease, Juvenile Huntington's Disease (JHD). Without further ado, let's begin!

 To understand what JHD is we first have to understand exactly what Huntington's disease (HD) is. Huntington's disease is a neurological disorder that begins in the Central Nervous System (CNS), which is the nervous system within your brain and spinal cord. This system helps process touch, feelings, and other senses and sends back responses on how to take action in response to them. The CNS also works on sending back responses on how to deal with issues and circumstances within the body. Inside the nervous system, some genes contain DNA. These DNA each have a certain "code" that dictates functions within the body. Why is this relevant? Well in the case of HD one particular gene is the root cause of this disease. It is known as ... the Huntingtin gene. On its own this gene isn't bad, in fact, it's vital for human function. However, the true issue with this gene comes from a certain mutation within it. Inside the DNA there are nucleotide bases which are the equivalent to the code for the DNA. These are adenine (A), cytosine (C), guanine (G), and thymine (T). One of the codes these bases make up is the CAG which is an essential component of the Huntingtin gene. This code has a certain number of repeats within the gene which decide how much of it is needed for the gene to do what is needed. However, in the case of HD, this code repeats too many times specifically over 35 times. Yet, the gene itself is not the issue rather it is what the gene helps create. When a certain function in the body needs help from this gene a certain process begins. It starts with the messenger RNA (mRNA)-which is equivalent to a postal carrier within the body- coming and copying or transcribing the gene and bringing it to the cytoplasm where it is turned into a protein. This protein then goes and helps the function within the body. In most cases, this happens normally and consistently and helps the body stay productive and healthy. However, in the case of HD, this protein has too many CAG repeats which turn into a part of the protein called "glutamine". Once turned into a protein the CAG produces a large string of glutamine called an expanded polyglutamine which is where the real issue sets in. This glutamine causes the protein to not be able to function by crowding it too much and not giving it enough space to properly carry out its function or for the other parts of the protein to thrive. Because this protein is so vital in the well-being of the body, having it not function properly puts the body in severe jeopardy. Because it is the same gene being copied again and again the same protein spreads throughout the body causing issues such as motor and cognitive loss and emotional distress. 

    Yet that is only for the adult version of HD. JHD is a type of HD that applies to people below the age of 20. This disease is much more rare with an estimated amount of 5-10% of all HD cases being JHD. However, the issue with this disease is its severity. This disease has more than 60 repeats of the CAG which causes the disease to expand rapidly and dangerously. The estimated life span after being diagnosed with this disease is 10-15 years. Usually, this disease is passed down genetically from a parent with HD. Each child of that parent (usually the father) has a 50% chance of getting the disease. However, the symptoms of this disease are much worse. This disease causes severe forms of depression, loss of cognitive function, and chorea which causes uncontrolled movements within the body. The worst part is that there is no cure. This is due to several factors. First off, due to it being a neurodegenerative disease very little information exists of it. Continuing, because it is so rare it is often misdiagnosed until it is too late. Lastly, since its main target is juveniles it is hard to run experimental testing due to ethics concerns. Most approved therapies only apply to HD and even those are scarce. For the most part therapy for this disease is symptomatic meaning it tries to help with the symptoms such as depression or chorea rather than targeting the gene that causes this issue originally. Further science will have to be developed before a finite therapy can be used for this disease. 

    Anyway, that is all for today's scientific explorers! While that has been a more heavy topic than usually handled on this blog I still consider it necessary to discuss. In fact, I am doing a research project on this currently and find it a very interesting and important topic to discuss. I most likely will dive deeper into this disease in later blogs but we shall determine that soon. So, thanks for reading and to leave you with a question: What is something you believe needs more research whether it is from science or not? Thank you for reading, I hope you learned something new, and see you next week!