What causes ALD? Who gets it?
ALD is an inherited genetic disorder linked to the X sex chromosome. Because of the way genetic inheritance works, only boys have the most severe form of ALD. The disorder leaves the body unable to break down big fat molecules, either ones the body makes itself or ones that enter the body through food. Recent research shows that this is most likely due to a carrier protein that fails to work correctly and carry the fat molecules to where they would be broken down. The fat molecules build up and clog up cells, and hurt nerve cells in the brain and spinal cord.
Scientists now have a way of examining a woman's ALD gene to see if it's abnormal. This way, a woman who may have inherited an abnormal gene will know for certain whether or not she has it (is a carrier) and could pass it on to her children.
Do all boys with ALD die?
There are several forms that ALD can take. The most devastating type, what Lorenzo Odone has, is the childhood cerebral form, meaning that nerves in the brain are destroyed. About 35-40% of all cases of ALD are this type, which usually appears between 4 and 8 years of age in boys. These boys will become totally disabled in 6 months to 2 years, and will die sometime after.
ALD can also appear like multiple sclerosis, in that there is a gradual loss of function in the body but without the severe brain damage of the cerebral type. This second form is called adrenomyeloneuropathy (AMN), represents about 40-45% of all ALD cases, and affects men in their twenties or middle age.
Because adrenoleukodystrophy damages the adrenal glands, the disorder can begin as Addison's disease. This represents about 10% of all ALD cases, and affects males between 2 years of age and adulthood. Young men with this form usually also develop AMN by middle age. Boys diagnosed with Addison's disease are usually tested to see if ALD is at the root of the problem.
Can ALD be cured?
Unfortunately, there is as yet no complete cure for cerebral ALD. However, there are several methods being tried that seem to slow down the destruction of the disease. One method is the use of "Lorenzo's oil," made from olive and rapeseed oil, and a very low fat diet. Unfortunately, Lorenzo's oil has not proven to be as effective as first thought. Researchers are still trying to understand the complex relationships among fats in the body, and how Lorenzo's oil could be further modified to be more effective.
A second treatment, being tested experimentally, is an anticholesterol drug called Lovastatin. Researchers aren't clear exactly why this drug seems to help, but are working on understanding the processes involved.
A third method for treating cerebral ALD is bone marrow transplant. The idea is to replace cells that have a defective ALD gene with cells that have a normal ALD gene and will break down fats.
As for adrenomyeloneuropathy (AMN), no treatment has yet been developed. If an adrenal disorder like Addison's disease is present, long-term hormone replacement provides treatment.
How is Lorenzo doing? Is he still surviving?
Lorenzo Odone turned 27 years old on May 29, 2005. He is "holding his own," said his father, Augusto Odone, in an interview with The Washington Post in 2003. "He looks healthy, but he hasn't recovered any functions in a big way," he added. Lorenzo is almost totally paralyzed. Unfortunately his mother, Michaela (portrayed in the movie by Susan Sarandon), died June 10, 2000, of lung cancer.
- GeneClinics (1999). X-Linked Adrenoleukodystrophy.
- Johns Hopkins Medical Institutions (Oct. 28, 1998). New test spots ALD carriers with near-perfect accuracy.
- King5.com (2000). 'Lorenzo's Oil' mother Michaela Odone dies. Reprinted from The Washington Post, June 11, 2000.
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