Adrenoleukodystrophy and its effects

Adrenoleukodystrophy (ALD) is a rare X-linked disease that attacks the central nervous system and breaks down the coating of nerve cells in the brain, called the myelin sheath. It has been discovered that mutations in the ABCD1 gene are linked to cause ALD. Patients who have ALD have very long chains of saturated fatty acids (VLCFA) that accumulate in the brain and in the adrenal cortex. ALD generally affects about 1 in every 100,000 boys between the ages of 4-8. About 1 in every 20,000 people in the world are either carrying the disease or they have been diagnosed with it. 90% of males who have ALD also have Addison’s disease. ALD and Addison’s disease paired together drastically effect both the physical and cognitive development of the patient throughout their lifespan. There are three different forms of ALD that all take place at a different point in the lifespan. The first is called Neonatal Adrenoleukodystrophy (NALD). This form of the disease belongs to the group called Peroxisomal Biogenesis disorders. But this is still an X-linked disease and relates to the other forms of ALD because it has the same effect on the body internally and externally. NALD is present in newborns and infants. This form damages the white matter of the brain and impairs the adrenal glands. The adrenal glands are the organ that produces the hormone cortisol; this hormone is used in the breakdown of the VLCFA. Symptoms of this include; going cross eyed, deafness and blindness. In most cases when this form of the disease is diagnosed, the patient does not live more than 4 months. The second form is the most prominent and the most severe; it is the childhood cerebral form and is called Adrenoleukodystrophy (ALD). This is form of the disease attacks between the ages of 4-8. The patient is given between 6 months to 2 years to live after diagnosis. Symptoms include: blindness, paralysis, deafness and decrease in fine motor skills such as walking and talking. The final form of this disease is called Adrenomyeloneuropathy (AMN). This is the adult-onset form of this disease and is also the mildest form. It affects males between the ages of 21 and 35. About 50% of women who are carriers of this disease will develop a very mild form of AMN. This form of ALD progresses slower than either of the other forms, symptoms include; stiffness, weakness, paralysis of the lower body and blindness. Patients are generally given between 4-8 years after diagnosis, depending on how quickly the disease sets in. ALD is very hard to diagnose at any point in the lifespan, because the onset signs and symptoms are very similar to that of several other types of diseases and mental illnesses. Multiple sclerosis often gets mistaken for ALD because it has the same physical effect on the body. Depending on how early in the patient’s development the disease is diagnosed, the prognosis varies along with the treatment options that are available. For example, if the disease is caught before any symptoms have occurred, then treatment can begin immediately and the patient has a much great survival rate than that of a patient who has already begun to go blind. But, in order to fully understand this complex disease, it is best to first understand how it is contracted. ALD is a rare famial X-linked recessive disease. This means that it is carried by women and passed off to their offspring. During pregnancy meiosis takes place, this is where the mother gives away an X-chromosome and the father will either give a Y-chromosome or an X-chromosome. A recessive trait can only be expressed if the dominant form is not present. This means that females can not develop ALD because they have two X-chromosomes, so the dominate form is always present in females. A male with ALD would not pass on their recessive allele to their child because they would most likely pass away from the disease before being able