Von Recklinghausen's Disease Diagnosis

QUESTION: Although we have no history of an illness called Von
Recklinghausen's disease in our family, it has now appeared for the first
time. We have read that it is an inherited condition, and can't understand
how this occurred. Could the diagnosis be wrong? Will you please help us?
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ANSWER: Your information is essentially correct. Von Recklinghausen's
Disease (or neurofibromatosis) is named after the doctor who first described
it in 1882. Although there are many symptoms, the most common is the
development of skin lesions composed of nerve and fiber tissue, which form
into tumors. The disease is mild in most cases, and patients may live a
normal life. It is an inherited condition and is one of the most common of
the diseases classified as genetic disorders. About 1 baby in 3,000 born in
the United States develops neurofibromatosis (NF) and about 100,000 Americans
are affected by it. It is caused by a single abnormal gene, which produces
the disease whenever it is present. It is therefore called a dominant gene,
since it over comes the influence of the normal gene which is also present as
one of the pair of genes that occupy the same place in the genetic makeup.
However, this abnormal gene may have been newly formed by a process known as
mutation, rather than inherited. About 50 percent of NF cases seem to occur
in this fashion, and this is the probable explanation for the circumstances in
your family. The disease produced by a newly mutated gene is in all ways
identical to that which occurs when the gene is inherited. It will also be
passed on in the same way, and each child of a parent with NF has a 50-50
chance of inheriting the disease, and developing at least some of the
characteristics of the disease. While there are no methods to prevent the
disease, and no prenatal tests available to discover its presence in the
unborn, there are procedures and techniques to treat its effects.