What Is Huntington'S Disease
Huntington's disease is characterized by chorea and dementia. It is inherited in an autosomal dominant manner and occurs throughout the world in all ethnic groups, with a prevalence rate of about 5 per 100,000.
Huntington’s disease (HD) is a devastating, progressive disorder of the brain that leads to uncontrolled movements, emotional instability, and loss of intellectual faculties. Huntington’s disease results from the genetically programmed degeneration of brain cells. Specifically affected early in the disease are cells of the basal ganglia, a structure deep in the center of the brain where movement is coordinated. Later, cells of the brain’s outer surface, or cortex, which control the functions of thought, perception, and memory are attacked. The defective gene unleashes its destructive forces most often when people are between the ages of thirty five and forty five years of age, although, in some instances, those younger than twenty or older than sixty are not exempt from the dreaded onset of symptoms.
The disease is characterized by chorea and dementia. It is inherited in an autosomal dominant manner and occurs throughout the world, in all ethnic groups, with a prevalence rate of about five per 100,000. The gene responsible for the disease has been located on the short arm of chromosome Number 4.
An affected parent can pass Huntington’s disease along to his or her offspring, and each child of a parent has a fifty percent chance of inheriting the HD gene and developing the disease. How the flawed gene causes the brain to degenerate remains a mystery that scientists are seeking to solve. The first signs of Huntington’s disease are subtle – a tic here, a twitch there, unexplained fluctuations of mood, an awareness of being clumsy, depressed, or more irritable than usual. There is a slurring and slowing of speech. Diagnosis at this early stage, however, is particularly difficult, since symptoms may be indistinguishable from normal variations in mood and behavior or from changes induced by other causes.
During the ten to twenty year span of the disease, a spectrum of progressively worsening symptoms appears and advances irreversibly, from uncontrollable muscle spasms to mental incompetence. Ultimately, HD confines people to wheelchairs and beds, leaving them unaware of their surroundings. The long-endured emotional and financial burden to an HD patient’s loved ones, some of whom may risk themselves and previewing their own futures, expands the tragedy. Yet there is substantial reason for hope that biomedical research will make this truly horrible disorder