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Types of VHL
by Berton Zbar, M.D., U.S. National Cancer Institute, Frederick, Maryland
One of the major goals of our research program has been to identify the changes in the
gene (mutations) that produce VHL. We have identified mutations in 85/114 (75%) of VHL
families. This area of mutation research has provided an enormous amount of new
information about VHL. I will summarize this information in this article.
Perhaps the most striking observation is that there appear to be three types of von
Hippel-Lindau disease. VHL type 1 is the commonest form of the disease and is
characterized by a tendency to develop tumors in the eyes, brain, spinal cord, kidney and
pancreas. VHL type 2 is less common. VHL type 2 differs from type 1 in that affected
family members may develop pheochromocytomas. VHL type 2 is further divided into types 2A
and 2B. Individuals in families with VHL type 2A develop pheochromocytomas, but not kidney
cancer (this type of VHL is uncommon). Individuals in families with VHL type 2B develop
pheochromocytomas and kidney cancer.
NCI classification of von Hippel-Lindau disease
Type: Clinical Characteristic
- 1: without pheochromocytoma
- 2: with pheochromocytoma
- 2A: without renal cell carcinoma or pancreatic cysts
- 2B: with renal cell carcinoma and pancreatic cysts
This classification was based on studies of the mutations in a large number of VHL
families. Families with more than 25 affected individuals were particularly useful in
identifying what tumors occur and what tumors do not occur with particular mutations.
The spectrum of tumors that occur in a particular VHL family can be described as the phenotype.1
One major result of our work is that we now know what types of tumors accompany particular
VHL mutations. For example, a mutation at position 505 in the VHL gene that changes the
DNA building block T to C is associated with VHL type 2A, that is eye, brain and adrenal
tumors but not kidney or pancreatic tumors. For another example, a mutation at position
712 or 713 in the VHL gene that changes the DNA building block C to T, or G to A, is
associated with VHL type 2B, that is eye, brain, kidney, adrenal and pancreas tumors. From
the mutation in the VHL gene, one can make informed predictions as to which tumors will
develop in a particular family. We are gathering together mutation data from families from
research workers in the U.S., Great Britain, Europe and Japan. This information when
combined with phenotype will be useful to investigators trying to predict disease
manifestations.
One of the most striking observations to emerge from studies of mutations of the VHL
gene involves the finding of exactly the same mutation in families that are not thought to
be related. This situation can come about in two ways: (1) the mutation has occurred
several times in the population; (2) the families with the identical mutation are in fact
related, they have a distant common ancestor, but are unaware of this fact.
We have had examples of both situations in our studies. There are 14 families in
Germany and 2 German families living in Pennsylvania that have the identical VHL mutation.
The evidence suggests that these families have a common ancestor with a VHL mutation.
There are families with VHL from several different countries that have the identical
712-713 mutation. The evidence suggests that this mutation developed independently in
these populations.
This information is published in the December 14, 1994, issue of Human Mutation.
Explore the Web service of the U.S. National Cancer
Institute
1. Phenotype: The entire physical makeup of an individual:
hair, eye color, and in VHL, the types of tumors present in the family.
Reprinted from the VHL Family Forum, newsletter of the VHL Family Alliance, ISSN
1066-4130, March 1995. Further information is available from the VHL Family Alliance, info@vhl.org.
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