____ ____ of Huntington's disease usually begin with arm jerks and facial twitches. Then tremors spread to other parts of the body and develop into writhing.
Gradually, in Huntington's the tremors interfere more and more with walking, speech, and other ____ ____. The ability to learn and improve new movements f is especially limited.
The Huntington's disorder is associated with gradual, extensive ____ ____, especially in the caudate nucleus, putamen, and globus pallidus but also in the cerebral cortex.
People with Huntington's disease also suffer ____ ____, including depression, sleep disorders, memory impairment, anxiety, hallucinations and delusions, poor judgment, alcoholism, drug abuse, and sexual disorders ranging from complete unresponsiveness to indiscriminate promiscuity.
Deficits in ____ and ____ usually proceed the motor symptoms in Huntington's.
memory and reasoning
Occasionally, individuals in the early stages of Huntington's disease are misdiagnosed as having ____.
Huntingtons disease most often appears between the ages of __ and __, although onset can occur at any time from early childhood to old age.
30 and 50
Once the symptoms of Huntington's emerge, both the psychological and the motor symptoms grow ____ ____ and culminate in death.
Huntington's disease results from a dominant gene on ____ __.
As a rule, a mutant gene that causes the loss of a function is ____. The fact the the Huntington's gene is dominant implies that it produces the gain of some undesirable function.
The critical area of the gene chromosome #4 includes a sequence of bases C-A-G (cytosine, adenine, guanine), which is repeated __ to __ times in most people. That repetition produces a string of __ to __ glutamines in the resulting protein.
11 to 24
People with up to __ C-A-G repetitions are considered safe from Huntington's disease. People with __ or more repetitions are likely to get the disease. The more C-A-G repetitions someone has, the earlier the probable onset of the disease.
35 : 39
A ____ ____ can predict not only whether a person will get Huntington's disease but also approximately when.
Variant forms of genes controlling glutamate receptors do not produce Huntington's disease by themselves, but they influence the age of ____ of ____.
onset of symptoms
For people with later onset of Huntington's, the role of ____ is weaker or less certain.
Indentification of the gene for Huntingtons disease led to the discovery of the protein that is codes, which has been designated ____.
Huntingtin occurs ____ the human body, although it's mutant form produces no known harm outside the brain.
Within the brain huntingtin occurs ____ neurons, not on their membranes. The mutant form impairs neurons in several ways.
In the early stages of the disease, huntingtin increases ____ ____, sometimes causing overstimulation of the target cells. Later, the protein forms clusters that impair the neurons mitochondria. It also impairs the transport of chemicals down the axon.
Several drugs block the glutamine chains from ____.
Another drug interferes with the RNA that enables ____ of the huntingtin gene.
_____ are effective if injected into the brain, although that is not an option for humans. (Neurotrophins do not cross the blood-brain barrier)
A more promising option is drugs that ____ the brain to make more neurotrophins itself.
People with Huntington's show disrupted circadian patterns and poor sleep as well as impairments in learning and memory. Giving them a daily ____ ____ improved their sleep, learning and memory.