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| The image above shows how widespread the death of brain tissue can be in Huntington's disease patients. Image Credit: the University of Alberta |
Huntington's disease is a heritable condition with onset of dementia (cognitive decline) and chorea (jerky and involuntary movements) occurring around middle age. The passing of Huntington's disease from one generation to the next follows the rules of autosomal dominance which means everyone with the Huntington's gene will have the disease and if their partner is healthy then their children have a 50% chance of having the gene passed onto them. The gene itself codes for a protein that is mutated in Huntington's patients such that there an abnormally large number of repetitions of a particular sequence of nucleotides (DNA building blocks): CAD. This repetition leads to the creation of a huge protein called "huntingtin" which will accumulate in the brain and slowly cause damage. What can be so striking and heartbreaking about this disease is the young age that symptoms begin and how early most patients will die. In the video below Daniel Mundy can be seen struggling with chorea while going through daily activities like walking, shaving, and describing his daughter.
Because of Daniel's affliction his daughter is at risk of developing his disease. But there is more than that: if she does get sick she will likely develop symptoms earlier and they will be more severe. This is due to a phenomenon in genetics called "anticipation" where the number of pathogenic repeats increases with each generation. One finds anticipation in many disorders that stem from trinucleotide repeats (CAD in Huntington's) including Myotonic Dystrophy and maybe even Crohn's disease. Integrating the concept of genetic anticipation into a physician's assessment and history-taking could lead to a more accurate and effective diagnosis, prognosis, and treatment plan.
Sources:
Merck Manual Professional Edition: Huntington Disease
University of Alberta: Huntington breakthrough
National Institutes of Health Genetics Home Reference: Anticipation
Wikipedia: Anticipation (genetics)
thanks for this really informative post! I had no idea about the phenomenon called "anticipation". It really makes the entire disorder even more severe and gruesome (in my eyes at least). I really hope that one day we can find a cure for diseases like this.
ReplyDeleteI'm glad you learned something, Bonnie! And I agree with your sentiment - heritable diseases (and especially those with anticipation) are really tragic. I hope a cure isn't too far out. If we can really nail down early gene sequencing and therapy then maybe we'll be able to test at risk fetuses and infants and knock out some of the CAD repeats that do so much damage.
DeleteHey Nick! Thank you for this post on Huntington's Disease! I found it very informative, as I have heard about this disease but was not aware of the specifics. Going off of what Bonnie said, the "anticipation" aspect of the disease has serious implications for those who suffer Huntington's disease and wish to have children. I wonder if in the future genetic testing or selection will be utilized with couples carrying Huntington's disease to ensure that the child of a patient suffering from Huntington's disease do not have to suffer through an even more severe form of the disease. The often controversial topic of genetic testing and selection for traits seems like it could be beneficial in avoiding the "anticipation" factor of this disease in offspring.
ReplyDeleteYour comment really gets at the heart of an interesting aspect of Huntington's Disease. In fact my post was originally going to be about the ethics of Huntington's. The disease is considered prototypical in certain situations and often used in discussions about where to draw the moral and legal lines in issues like prenatal diagnosis and even eugenics. I've included a Wikipedia link that discusses this issues in more detail.
Deletehttp://en.wikipedia.org/wiki/Huntington's_disease#Ethics
I, like Bonnie, wasn't aware of the phenomenon "anticipation". I find in really interesting knowing that with each generation the disease gets "smarter" and essentially takes over and displays its effects more quickly and with increasing severity. Additionally, I really liked how you included a picture of the brain, it really gives perspective on how much damage is done.
ReplyDeleteI'm glad there was something new for you! Regarding the picture there's something interesting I wanted to say but didn't have room for in my post. The striatum is usually the first brain structure affected by Huntington's Disease. The striatum plays important roles in movement, mood/emotion, and parts of cognition. This explains why altered mood and movement are often the first symptoms. Part of the changes in cognitive function can also lead to loss of inhibition so Huntington's patients are often found to have increased problems with drugs, gambling, or hypersexuality. In the picture you can see a marked decreases in the size of the striatum but I've included a link to a picture that focuses on this area a little more.
DeleteSource: http://en.wikipedia.org/wiki/Huntington's_disease#Mechanism
Image: http://dailydiseasesanddisorders.tumblr.com/post/6040194582/huntingtons-disease
I’m glad you put that video in of Daniel showing the effects of Huntington’s. Sometimes reading articles about mechanisms and trials can seem mundane but when we see that these diseases can hugely impact a human being’s life it really shows the importance of why we study what we study. I have never worked in a hospital so I don’t see these diseases effect people so it is important for me to always keep it in mind while studying.
ReplyDeleteI'm really glad you appreciated the video. Its definitely too easy to lose sight of the human aspect things while studying physiology and medicine.
DeleteThe video made the description come alive and real. I agree that just reading articles makes us become a little distant to what the people actually go through and this is a great way to remind us. I'm really glad I recently had genetics so I can grasp the concept of anticipation with the genetics. It is definitely something to consider with genetic testing becoming more accessible.
ReplyDeleteThanks for the comment! You made me curious about the current state of genetic testing so I looked it up. I'll copy a link here in case you're also curious. The date indicates it was updated within the last week or two.
Deletehttp://ghr.nlm.nih.gov/handbook/testing/costresults
Going off of what Madison said, I believe that would be a great way to help the future generations and ease the worries that would burden the parents that are affected by the gene. But from what I remember from bioethics last semester, we talked about a man (whose name I can't remember) who had set up a research foundation for Huntington's disease because his wife had been diagnosed with it and he had two daughters whom he wanted to protect. And correct me if I'm wrong but while he wasn't able to come up with a method of prevention or a cure, there was talk about how a specific portion of a person's dna could be inspected for the huntington gene. If the person was positive for the gene, they would eventually have huntington's disease. And if the person was negative for the gene, we know that that would mean that the person would be in the clear. So anyway, his two daughters were both given the option of checking their dna for the gene but they had decided against it. They thought that if they were declared negative for the gene, it would be as if a weight was lifted from their shoulders. But on the other hand, if they were declared positive, they wouldn't be able to live their lives to fullest extent knowing that at any time, the huntington's disease could hit them. Their decision was incredibly admirable but it is still heart-breaking to know that many people are being affected by the disease everyday. I hope that our medical and scientific/technological field can make great advancements in finding a cure for huntington's disease soon!
ReplyDeleteSydney, I appreciate your comment and your walk-through of the bioethics example. The daughters' choices were interesting and it highlights how individualized our responses can be to such things. I imagine I would want to know because if I was positive for the disease I would have different career/life goals. And according to my research no, there is no cure or prevention methods.
DeleteI also have never learned about "anticipation", and on a personal level I couldn't imagine having a son/ daughter and fearing that they would develop the disease with symptoms even more severely than myself. My dads cousins are susceptible to Huntingtons, and both don't want to be genetically tested too see if their carriers but they differ in the fact that one had children and one choose not too. This is a really hard situation to be in, but if you were in the situation where you know you could pass down this disease to your child, would you have children? Is it ethical to gamble the 50/50 chance that your child will have this disease?
ReplyDeleteLike I said above I would want to get tested if I was at risk. As far as the ethics go, I think someone who may have a child or is planning to have a child should get tested. I don't think they should be forced to but I would advise a person in this situation to think about adopting unless they get tested and come back negative. I feel this way because of how hard it could be on the child and the parents if Huntington's was passed down.
DeleteThanks Nick! I guess one advantage we have in cases like Huntingtons disease is that, as you stated toward the end of your post, with proper analysis and a family history, we can see it coming from years away. As scary and limiting as it may seem, this could be a real advantage to people, giving themselves a chance to make lifestyle changes that will inhibit them less and make the most of their abilities. If treatments require prolonged periods, this is one case where long term therapies toward mitigating or preventing morbidity and mortality may have more of a chance.
ReplyDeleteI totally agree. I know that if I was diagnosed I would radically change my career and life goals and focus on traveling and the like. As for your point about prolonged treatment - I think this is especially pertinent since gene therapy has a real shot at being preventative. Potentially even embryos or fetuses could be targeted!
DeleteVery interesting post Nick. like many of the other students, I also wasn't aware of the phenomenon of anticipation, although it does make sense. I think the most terrible part about this disease is that it is autosomal dominant, so the risk of getting the disease is much higher... if one parent has it, then the child will have a 50% chance of acquiring the gene too. This brings into question the ethics of having children if an individual is sick with the disease: is it really fair to bring a child into this world when they have a 50% chance of acquiring the gene for this horrible disease?
ReplyDeleteThanks for your thoughts on the topic - there are some really tough dilemmas here and each person has to make their own ethical calculation when put in this hard spot. If you're interested I posted some opinions and links to more information on the topic in my comments above.
DeleteThe video you posted brings to attention an issue many couples face when one partner either has or carries a genetic disease. Obviously in most cases the couple intends to reproduce, but if a genetic disease is thrown into play the decision to have children becomes difficult. Hopefully Daniel's daughter does not develop Huntington's disease as the "anticipation" causes the symptoms to come earlier and be more intense.
ReplyDeleteDoes anyone still doubt natural herbs? I have seen the great importance of natural herbs and the wonderful work they have done in people's lives. I wonder why people still spend their money on English medicine when natural herbs can cure all kinds of mental diseases. I have seen it with my own eyes. My dad and aunt were cured from Huntington disease with Dr Bharet herbal medicine. He used BUJA herbal medicine to cure my dad and aunt from Huntington disease, I know it is hard to believe but am a living testimony. My dad was diagnosed with Huntington's disease in 2016, we have made use of all western medication yet no improvement and his doctors said there is no cure yet but still carrying out research, my dad experienced depression, anxiety and memory lapses that made him hallucinate always, he speaks to himself often and that made me shed tears each night that passes by. 2019 I searched through the internet for a solution and i came across a comment on a blog written by [Robert Jane] saying she was cured of Huntington disease that she suffered from for 8years. Without wasting time I quickly contacted Dr Bharat whose name was mentioned in the comment Via his email. He asked me questions which I answered correctly he sent his herbal medicine to us here in Ireland through DHL, in less than one month I started seeing positive improvement on my Dad's health so I introduced the medication to my aunt as well, is been 4 years now, my dad and aunt are living their best life again. Though i gave the medication as i was instructed. My dad and aunt are Huntington disease negative after the medication, Huntington disease is completely gone from my family lineage. With Bharat herbal medicine called BUJA Huntington patients can smile again. For those with Huntington disease or having their love ones diagnosed with Huntington's disease contact Dr Bharat now via dr.bharatkings@gmail.com you will come back to testify
ReplyDeleteI want to make this testimony public and as a sign of gratitude to Dr Bharat. On how he saved my husband from Huntington's disease with his herbal medicine called BUJA, i decided to reach out to those still suffering from this disease.
ReplyDeleteMy husband suffered Huntington disease and it was really tough and heartbreaking for me because he was all i have and the symptoms were terrible, my husband experience hallucination, depression, anxiety, abnormality walking, involuntary movement and memory impairment. We tried various therapies prescribed by our neurologist but none could cure him instead the situation got worsen each day that passes by. I spent much money yet no improvement, I really do not want my husband to die so i searched for a cure on the internet and i bumped into a testimony of (Ronda Jasil) who got cured from Huntington's disease. and she left the e-mail address of the Herbal doctor who has the cure of Huntington disease. I never imagined Huntington's disease has a cure until i contacted him and he assured me my husband will be fine. I got the herbal medication he recommended and my husband used it and in one month we started seeing improvement, now is been 1year and 6 months my husband is okay and full of life again. Huntington's disease has a cure and it is a herbal medicine called BUJA. contact doctor Bharat now on dr.bharatkings@gmail.com Thanks for reading my testimony
Read carefully, it's said that Huntington disease has no cure, yes with the western medication but not with herbal medicine, my daughter's situation made me to realize that with doctor Bharat herbal medicine it can be cured.. In 2014 she experienced difficulty in concentrating, memory lapses and depression, at first I thought it was stressed from her place of work until I took her to hospital and the doctor made me to understand that it's juvenile Huntington disease because she is still in her late 20s, which she inherited from my late husband that died of the same disease, the doctor told me it has no cure, but gave her some medicine which I noticed that it has side effects, my daughter situation got worst each day that passes, she was the best at her place of work, now a shadow of her self because of this deadly disease, she speaks to herself often, she was really going insane, I do not want to lose my daughter the same way I lost her father, in 2018 I carried out research on internet and bumped into a comment of a lady that got cured of Huntington disease, without wasting time I contacted doctor Bharat whose name was mentioned in the comment, now is been 3 years my daughter is living her best life again, for those that have the disease or have any love one suffering from Huntington disease, contact doctor Bharat via dr.bharatkings@gmail.com
ReplyDeleteHi everyone, this is good news, a perfect and greats one. My daughter of 38years who has suffered of Huntington's disease for 2 and half years has been cure by a Herbal doctor called Dr Bharat who uses herbal and traditional supplements to cure people. I have spent so much money on my daughter's health for years but no improvement. A friend told me about this herbal man who cure people with herbal supplements. he cures all mental sickness, diseases, viruses, and infections with his different herbal curing supplement .The result that declares my daughter healed was from a hospital here in USA, And the results of the test says my daughter was okay. Dr Bharat said my daughter will be heal in 8weeks(2 months) if she uses the supplements as directed. In 2 weeks i started seeing great improvement, exactly 8weeks we went to confirm from the central hospital and several test that was done says my daughter is Huntington's disease negative. She got cured with Dr Bharat herbal supplements, this is super amazing. My daughter is fully okay and back to her work again. I can boldly say that Huntington's disease is 100% curable with doctor Bharat herbal supplements, is real, anyone with Huntington's disease or have love ones that is suffering from Huntington's disease should contact doctor Bharath now on his mail. dr.bharatkings@gmail.com or WhatsApp him on +393509392854
ReplyDeleteRead carefully, it's said that Huntington disease has no cure, yes with the western medication but not with herbal supplement, my daughter's situation made me to realize that with doctor Bharat herbal supplement it can be cured. In 2014 she experienced difficulty in concentrating, memory lapses and depression, at first I thought it was stressed from her place of work until I took her to hospital and the doctor made me to understand that it's juvenile Huntington disease because she is still in her late 20s, which she inherited from my late husband that died of the same disease, the doctor told me it has no cure, but gave her some medicine which I noticed that it has side effects, my daughter situation got worst each day that passes, she was the best at her place of work, now a shadow of her self because of this deadly disease, she speaks to herself often, she was really going insane, I do not want to lose my daughter the same way I lost her father, in 2018 I carried out research on internet and bumped into a comment of a lady that got cured of Huntington disease, without wasting time I contacted doctor Bharat whose name was mentioned in the comment, now is been 3 years my daughter is living her best life again, for those that have the disease or have any love one suffering from Huntington disease, contact doctor Bharat via dr.bharatkings@gmail.com or Whatsapp him on: +393509392854
ReplyDeleteMake me a promise Phyna, my mother said. "Promise me you won't put me in a home or make me live with one of your sisters". It was a joke at the time when my mom was just starting to forget things. 07/10/2020 was the hardest day of my life. Watching my mom talk to herself, packing her things 4-5 times a day, saying she has to go home. It was heartbreaking. I broke down and cried with her a few times and then I realized how hard it must be on my dad too. He can't leave the house, he has to convince her that she lives in their house. I came to the decision to quit my job. My dad needs help. I live 6 hours away but instead of visiting my parents, I'll be visiting my husband. My mom has always been there for me and been my best friend so I want to be there for her. I keep telling myself that I can snap her out of it. I got her numerous medications including RISPERDAL(RISPERIDONE), HALDOL(HALOPPERIDOL), THORAZINE(CHLORPROMAZINE) and TETRABENAZINE(XENAZINE) and DEUTETRABENAZINE (AUSTEDO) instead of helping her, they almost destroyed her due to the side effects. As I was reading more about Huntington's Disease on the internet, I met with some comments of people testifying about Dr. Bharat and his BUJAA HERBAL SUPPLEMENTS that it works for Huntington's. I contacted the doctor immediately and explained my mother's condition to him, he assured me that my mom will be fine and her memory will come back to normal. I ordered his Herbal Supplements and it was delivered to me here in Canada by DHL courier company in less than a week with instructions on how to use them attached in the package. After 3 weeks of using these herbs, we began to see improvement, after 6 months my mom was better, and it's been 2 years now and my mom is completely free from this horrible disease called huntington's. In case your loved one is suffering from huntington's disease I will advise you to use BUJAA HERBAL SUPPLEMENTS it may also help you. You can contact Dr. Bharat via email; dr.bharatkings@gmail.com or Whatsapp him on: +393509392854
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