Adrenoleukodystrophy (ALD) is a rare X-linked disease characterized by accumulation of long fatty acid chains in the adrenal glands, brain, plasma and fibroblasts. This causes a degeneration of the myelin sheath that surrounds and protects the function of the nerve cells. Approximately 1 in 100,000 is affected. There are three basic forms of ALD: neonatal, childhood, and adult-onset. The neonatal form affects both males and females. It progresses rapidly and may lead to mental retardation, facial abnormalities, seizures, poor muscle tone, enlarged liver and adrenal dysfunction. The childhood onset is the most common and also the most severe form. Onset of the disease occurs around the ages of 4-10 years old. Symptoms include behavioral problems, poor memory and speech and vision loss, difficulty in swallowing and unsteadiness in gait. Childhood ALD generally results in total disability and possible death within ten years of onset. Childhood ALD primarily affects males.


Adult-onset ALD, also known as Adrenomyeloneuropathy, is milder and progresses much slower than childhood ALD. Symptoms become apparent around the ages of 21-35 years of age. Lower limbs are primarily affected and may become stiff, weak or completely paralyzed. Patients may also experience loss of coordination. Women who are carriers of ALD may show symptoms but they are usually much less pronounced.


There is no cure or treatment to reverse the effects of ALD. Affected individuals undergo physical therapy and counseling and are usually enrolled in special education. Genetic counseling is highly recommended for families with a history of ALD. The form of ALD may be determined through a comprehensive genetic analysis. Those with childhood or adult-onset ALD may take advantage of a new test called Pre-Implantation Genetic Diagnosis (PGD). PGD tests for genetic abnormalities and can determine the sex of an embryo prior to implantation. Through this mechanism, the chances of having an affected child is greatly reduced. Due to complex inheritance patterns of genetic disorders, an experienced genetic counselor can determine whether PGD will be beneficial. PGD can also test for other genetic conditions and is continually being improved to included more genetic diseases.