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[Stas]

a rare genetic condition that affect the nervous systems

It’s tough enough for a family to have someone suffer from a genetic disorder but to have three in the family is just heart-breaking. And that’s what the Shaffer family from Oregon is going through as their three young sons are treated for a rare genetic condition that affect the nervous systems. Two 8-year old twins and their younger brother have leukodystrophies (adrenoleukodystrophy or ALD), a disorder that causes damage to the membrane (myelin sheath) that surrounds nerve cells in the brain. Adrenoleukodystrophy is commonly inherited as an X-linked (or sex-linked) trait, as the gene is located on the X-chromosome and passed from mother to her children. If the mother is a carrier (say XX for one abnormal allele), then she will pass that defective gene to all her sons (XY). Her daughters will have a 50% chance of inheriting the defective X.
Although inherited at conception, the X-ALD can manifest in early childhood (age 4-10) or adulthood (age 21-35), but the onset in children is most severe. Symptoms include progressive stiffness, weakness or paralysis of the lower limbs, and deterioration in brain function. Carrier daughters exhibit the milder forms of the disease but the sons will experience the most severe symptoms because they don’t have the protection of one normal X allele.
"Most of the boys that have this disease look absolutely fine until they’re school aged, so 6 to 8, 10, then they develop progressive neurologic symptoms. Actually it’s a lethal disease. They tend to go downhill relatively quickly and die within a few years," said Dr. Paul Orchard of the University of Minnesota Amplatz Children’s Hospital.
The Shaffer boys were diagnosed early, so they have better prognosis for treatments. The family is staying at the Ronald McDonald House in Minnesota while they’re being treated. And you’re heart would just go out to these playful boys who have so much to go through at a young age.

[googlewoman]

Stas you the good fellow, have touched very good theme.



Adrenoleukodystrophy

Adrenoleukodystrophy, or ALD, is an x-linked metabolic disorder, characterized by progressive neurologic deterioration due to demyelination of the cerebral white matter. Brain function declines as the protective myelin sheath is gradually stripped from the brain’s nerve cells. Without that sheath, the neurons cannot conduct action potentials—in other words, they stop telling the muscles and other elements of the central nervous system what to do.

This sequence of events appears to be related to an abnormal accumulation of saturated very-long-chain fatty acids (VLCFA) in the serum and tissues of the central nervous system, which sets off an abnormal immune response that leads to demyelination. It is unclear exactly how this chain of events works, but scientists do know that it has its roots in genetics.

ALD is caused by a genetic abnormality, commonly referred to as a “genetic mutation”, affecting the X chromosome, otherwise known as an “x-linked” condition. Everyone has two sex chromosomes: women have two X chromosomes and men have an X and a Y chromosome. If a woman inherits the abnormal X chromosome, she still has a normal, second X chromosome to help balance out the affects of the mutation. Boys and men do not have a second X chromosome, so if they inherit this genetic abnormality, they will get the disease.

ALD takes several forms, which can vary widely in their severity and progression. They include:

Childhood cerebral demyelinating ALD. This is the most common form of ALD, representing about 45% of all ALD cases. It is characterized by an inflammatory process that destroys the myelin, causing relentless progressive deterioration to a vegetative state or death, usually within five years.

Adrenomyeloneuropathy. The majority of other cases of the disease occur as the adult form, known as AMN. In about half of the sons who inherit the mutated ALD gene, symptoms of the disease do not develop until young adulthood, and in general, they progress more slowly. Beginning in their 20s and 30s, these young men exhibit neurological based motor lesions in their extremities. These lesions progress over many years and are inevitably accompanied by moderate to severe handicap. In approximately one third of these patients the central nervous system also becomes involved. These young men undergo the same mental and physical deterioration as the previously described boys. The progress of the disease is slower, usually declining to a vegetative state and/or death in 5 years or longer. There is no effective treatment for the adult onset of ALD, which is commonly referred to as adrenomyeloneuropathy (AMN); rather, medication and therapies are employed in a palliative manner.

Addison’s disease. (Hypoadrenocorticism) Most boys and men with ALD/AMN have Addison’s disease, a disorder of the adrenal gland; in about 10% of ALD cases, this is the only clinical sign of the disorder. The adrenal glands produce a variety of hormones that control levels of sugar, sodium, and potassium in the body, and help it respond to stress. In Addison’s disease, the body produces insufficient levels of the adrenal hormone, which can be life-threatening. Fortunately, this aspect of ALD is easily treated, simply by taking a steroid pill daily (and adjusting the dose in times of stress or illness)

Female ALD. Although women who carry the ALD gene mutation do not generally develop the brain disease itself, some display mild symptoms of the disorder. These symptoms usually develop after age 35, and primarily include progressive stiffness, weakness, or paralysis of the lower limbs, numbness, pain in the joints, and urinary problems.

[googlewoman]

Alternative Names

Adrenoleukodystrophy; Adrenomyeloneuropathy; Addison disease; Childhood cerebral adrenoleukodystrophy; ALD; Schilder-Addison Complex


Causes

Adrenoleukodystrophy is passed down from parents to their children as an X-linked genetic trait. It therefore affects mostly males, although some women who are carriers can have milder forms of the disease. It affects approximately 1 in 20,000 people from all races.

The condition results in the buildup of very-long-chain fatty acids in the nervous system, adrenal gland, and testes, which disrupts normal activity. There are three major categories of disease:

* Childhood cerebral form -- appears in mid-childhood (at ages 4 - 8)
* Adrenomyelopathy --occurs in men in their 20s or later in life
* Impaired adrenal gland function (called Addison disease or Addison-like phenotype) -- adrenal gland does not produce enough steroid hormones


The list of signs and symptoms mentioned in various sources for Adrenoleukodystrophy includes the 46 symptoms listed below:

* Seizures
* Impaired motor function
* Impaired vision
* Swallowing difficulties
* Attention problems
* Cognitive impairment
* Behavioural impairment
* Adrenal atrophy
* Mental deterioration
* Aphasia
* Apraxia
* Progressive blindness
* Difficulty reading in children
* Difficulty writing in children
* Difficulty understanding speech in children
* Difficulty comprehending written material in children
* Leg stiffness
* Leg weakness
* Urinary disorders
* Adrenocortical insufficiency
* Increased skin pigmentation
* Brain sclerosis
* Brain demyelination
* Seizures
* Lack of control of voluntary leg movements
* Muscle weakness on one side of body
* Hypotension
* Reduced hormone production by testes
* Reduced hormone production by ovaries
* Adrenal insufficiency
* Anemia
* Mental retardation
* Cortical blindness
* Walking difficulty
* Fatigue
* Vomiting
* Aphasia
* Withdrawn state
* Emotional instability
* Aggressive outbursts
* Noncommunicative behavior
* Restlessness
* Abnormal behavior
* Weakness
* Retinal degeneration
* Enlarged liver

[Stas]

Medical Textbooks Online about Adrenoleukodystrophy
http://www.wrongdiagnosis.com/a/adrenoleukodystrophy/allbooks.htm
Very informative site