Huntington's disease

Examples of Huntington's disease in the following topics:

• Lethal Inheritance Patterns

  • An example of this in humans is Huntington's disease in which the nervous system gradually wastes away .
  • People who are heterozygous for the dominant Huntington allele (Hh) will inevitably develop the fatal disease.
  • However, the onset of Huntington's disease may not occur until age 40, at which point the afflicted persons may have already passed the allele to 50 percent of their offspring.
  • The neuron in the center of this micrograph (yellow) has nuclear inclusions characteristic of Huntington's disease (orange area in the center of the neuron).
  • Huntington's disease occurs when an abnormal dominant allele for the Huntington gene is present.

• Disorders of the Basal Ganglia

  • Basal ganglia disease refers to physical dysfunctions that occur when basal ganglia fail to suppress unwanted movements.
  • An example of a hypokinetic basal ganglia disease is Parkinsonism.
  • An example of a hyperkinetic basal ganglia disease is Huntington's Disease.
  • Huntington's disease is a hereditary disease that causes defects in behavior, cognition, and uncontrolled rapid, jerky movements.
  • Evidence shows that the basal ganglias in patients with Huntington's Disease show a decrease in activity of the mitochondrial pathway, complex II-III.

• The Role of the Basal Ganglia in Movement

  • The greatest source of insight into the functions of the basal ganglia has come from the study of two neurological disorders, Parkinson's disease and Huntington's disease.
  • Parkinson's disease involves the major loss of dopaminergic cells in the substantia nigra.
  • Huntington's disease involves the massive loss of medium spiny neurons in the striatum.
  • The symptoms of the two diseases are virtually opposite: Parkinson's disease is characterized by a gradual loss of the ability to initiate movement, whereas Huntington's disease is characterized by an inability to prevent parts of the body from moving unintentionally.
  • The immobility of patients with Parkingson's disease has sometimes been described as a paralysis of the will.

• Biochemical Products of Recombinant DNA Technology

  • Recombinant DNA technology, apart from being an important tool of scientific research, has also played a vital role in the diagnosis and treatment of various diseases, especially those belonging to genetic disorders.
  • Hereditary diseases carrier diagnosis: tests now available to determine if a person is carrying the gene for cystic fibrosis, the Tay-Sachs diseases, Huntington's disease or Duchenne muscular dystrophy.
  • Gene transfer from one organism to other: the advanced gene therapy can benefit people with cystic fibrosis, vascular disease, rheumatoid arthritis and specific types of cancers.

• Basal Ganglia

  • The most notable are Parkinson's disease, which involves degeneration of the melanin-pigmented dopamine-producing cells in the substantia nigra pars compacta (SNc), and Huntington's disease, which primarily involves damage to the striatum.
  • Basal ganglia dysfunction is also implicated in some other disorders of behavior control such as the Tourette's syndrome, ballismus (particularly hemibalismus), obsessive–compulsive disorder (OCD), and Wilson's disease (Hepatolenticular degeneration).
  • With the exception of Wilson's disease and hemiballismus, the neuropathological mechanisms underlying diseases of ganglia such as Parkinsons' and Huntington's are not very well understood or are at best still developing theories.

• Neurodegenerative Disorders

  • Alzheimer's disease and Parkinson's disease are both neurodegenerative disorders characterized by loss of nervous system functioning.
  • Neurodegenerative disorders include Huntington's disease, amyotrophic lateral sclerosis (ALS), Alzheimer's disease, other dementia disorders, and Parkinson's disease.
  • Parkinson's disease is also a neurodegenerative disease.
  • The disease probably results from a combination of genetic and environmental factors, similar to Alzheimer's disease .
  • Distinguish between the neurodegenerative disorders of Alzheimer's disease and Parkinson's disease

• Types and Functions of Proteins

  • Small changes in the amino acid sequence of a protein can cause devastating genetic diseases such as Huntington's disease or sickle cell anemia.

• Genetic Drift

  • As a result, the population expresses unusually high incidences of Huntington's disease (HD) and Fanconi anemia (FA), a genetic disorder known to cause blood marrow and congenital abnormalities, even cancer.

• Disease Severity and Duration

  • An acute disease is a short-lived disease, like the common cold.
  • A refractory disease is a disease that resists treatment, especially an individual case that resists treatment more than is normal for the specific disease in question.
  • A progressive disease is a disease whose typical natural course is the worsening of the disease until death, serious debility, or organ failure occurs.
  • Slowly progressive diseases are also chronic diseases; many are also degenerative diseases.
  • The opposite of progressive disease is stable disease or static disease: a medical condition that exists, but does not get better or worse.

• Autoimmune Diseases

  • Autoimmune diseases are an inappropriate immune response against tissues in the body.
  • Autoimmune diseases are commonly considered complex immune disorders.
  • While many autoimmune diseases are rare, collectively these diseases afflict millions of patients.
  • However, defects of one or more of these genes do not cause an autoimmune disease, but only predispose a person for an autoimmune disease.
  • The factors that trigger an autoimmune disease are still unknown.