Although anyone can develop HD, it tends to run in people of European descent (having family members who came from Europe). But the main factor is whether you have a parent with HD. If you do, you have a 50% chance of also having the disease.
You're usually only at risk of developing it if one of your parents has or had it. Both men and women can get it. If a parent has the Huntington's disease gene, there's a: 1 in 2 (50%) chance of each of their children developing the condition – affected children are also able to pass the gene to any children they have.
The age of onset of Huntington disease varies greatly from person to person, but most people develop it in their 30s or 40s. Huntington disease is a rare disorder. More than 15,000 Americans currently have the disease, but many more are at risk of developing it.
Huntington's disease is caused by a faulty gene. Cells in parts of the brain are very sensitive to the effects of the faulty gene. This makes them function poorly and eventually die. A parent with the Huntington's disease gene has one good copy of the gene and one faulty copy.
Myth 1: HD is a male disease. Fact: Both men and women can be born with the HD gene.
There have been reports that juvenile onset Huntington's chorea is almost always inherited from the father, and that late-onset Huntington's chorea is inherited more often from the mother than from the father.
An affected person usually inherits the altered gene from one affected parent. In rare cases, an individual with Huntington disease does not have a parent with the disorder.
Prevention of Huntington's disease
Because Huntington's is a genetic disease, you can't do anything to prevent it if you have inherited it. If you have a history of Huntington's disease in your family, you may wish to have genetic counseling before having children of your own.
Symptoms of Huntington's disease usually develop between ages 30 and 50, but they can appear as early as age 2 or as late as 80. The hallmark symptom of Huntington's disease is uncontrolled movement of the arms, legs, head, face and upper body.
Each child of a parent with HD has a 50 percent chance of inheriting the HD gene. A child who does not inherit the HD gene will not develop the disease, and generally, they cannot pass it on to their children or other future generations.
For example, if a child's grandparent has Huntington's disease, but the child's at-risk parent hasn't been tested, then the child has a 25% probability of having inherited the gene. If the parent doesn't have the expanded gene, then the risk drops from 25% to 0% - meaning there is no risk at all to the child.
Typical age at onset of symptoms is in the 40s1. The cause is a gene mutation in chromosome 4 with a CAG trinucleotide repeat of 35 or greater2. Repeat size can expand or contract with the next generation.
Familial prion disease may produce a diverse range of phenotypes, even within the same pedigree. It may resemble HD with prominent personality change, psychiatric symptoms and cognitive decline, chorea, rigidity, and dysarthria. Limb and truncal ataxia and seizures may be present.
Currently, there are no treatments available for Huntington's disease that change the course of the disease.
Once the symptoms start to affect your daily life, you will be diagnosed with active disease. The disease is staged based on your motor function and ability to complete everyday tasks. Typically, HD progresses for 10 to 30 years.
Late-onset (>59 years) Huntington's disease (HD) is rare, and information on the manifestations, disease course, and underlying genetics is scarce.
In Australia it is estimated that over 1,800 people have Huntington's Disease and approximately 9,000 are at risk (Huntington's NSW ACT website, 2019) with a reported prevalence rate in Australia which ranges from 4.5 per 100,000 to 6.5 per 100,000 (Pringsheim et al., 2012).
Delaying & Treatment of Symptoms
Eating well is also vital to keeping both the brain and body healthy. Just by eating right and exercising regularly, you can help to delay the onset or progression of symptoms. Keeping your brain active may also help, so do lots of puzzles like Sudoku.
In this first Asian study on survival in HD patients, the median survival from onset was 14.5 years. Although a direct comparison is not possible, it appears that the mean survival in our study is shorter that that reported by Rinaldi et al. [14] (20 years, 95% CI: 18.3–21.7). In a study by Pekmezovic et al.
The genetic risk to children
A person with a Huntington's disease affected parent has a 50% risk of having inherited the Huntington's disease gene. Each child of that person has a 25% chance of inheriting the condition. But this '25%' only applies while the person is untested.
Huntington's Disease (HD) is not fatal in itself. People with HD have a shorter life expectancy and die of other life-threatening complications related to this disease. Pneumonia and heart disease are the two leading causes of death for people with HD.
Symptoms typically emerge from age 30 to 50, but also can develop in children and older adults. Late-onset Huntington's, characterized by some as emerging after age 5o and others after age 60, is thought to be less severe than earlier onset Huntington's.