Neurofibromatosis (NF) - Boulder Valley School District
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Transcript Neurofibromatosis (NF) - Boulder Valley School District
Neurofibromatosis (NF)
aka “von Recklinghausen disease”
Brennan Coffey
Logan Ernst
Period 3
What is it?
• Neurofibromatosis is a class of genetic disorders
that causes tumors to grow in the nervous system
called neurofibromatoses
• The process begins in the myelin sheath that
coats the nerve cell
• it causes a transformation that eventually leads
to the growth of tumors that cause other
disorders that can be seen in abnormalities such
as skin changes and bone deformities
What is it?
• The disorder is most commonly inherited,
however there is a chance that a mutation could
develop and cause the disorder to arise
• nearly 30-50% of new cases arise out of random
mutation, not genetic inheritance
• There are currently 3 different types of NF, they
are NF type 1, NF type 2 and schwannomatosis
which used to be classified as a type of NF2, but
is more appropriately its own class
What is it?
NF1
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To diagnose NF, a doctor would look at
skin appearance
bone abnormalities
Tumors
in addition to this they would also consider
the predisposition to the disease as is
indicated by family history
What is it?
NF1
• Many of the color abnormalities are evident as
light brown spots on the skin
• two or more growths on the iris a tumor on the
optic nerve
• an abnormal head circumference, abnormal
developments of the spine, skull bone or tibia
• Symptoms for NF1 are generally mild and those
who suffer from it live normal and productive
lives, however there is a possibility NF1 is
severely debilitating and has cosmetic and
physiological repercussions
What is it?
NF2
• The difference between NF2 and NF1 is the
fact that NF2 has slower-growing tumors
• To diagnose NF2 doctors would look at the
eighth nerve tumors, development of
cataracts at an early age, or other nervous
system tumors and the relative growth of the
tumors
What is it?
Schwannomatosis
• Schwannomatosis is characterized as being
comprised of different cells than other tumors
(schwannomas)
• It is named for Theodor Schwann, a German
physiologist who is best known for his theory that
all animals consist of cells
• As these tumors cause pressure to neighboring
nerves, a very common symptom in diagnosis is
pain as the nerve develops and compresses
nearby tissues
What is it?
Schwannomatosis
• With NF2 and schwannomatosis there is more
danger as the cancer can grow to damage
nearby tissues such as cranial or cardiac
tissues which can have fatal corollaries in
addition to great pain
Inheritance
• The disease is autosomal dominant, meaning
that it affects both sexes equally
• It is not co-dominant so the only genotypes
that correspond with the disorder are RR, Rr
and rr, the homozygous recessive pair codes
for not having the disorder
Inheritance
• NF1 has a frequency of 1 in 3,000 and NF2 has a
frequency of 1 in 45,000 and Schwannomatosis
has a frequency of 1 in 40,000
• If a parent has NF, there is a 50-100% chance that
the child will inherit the trait
• There is no specific phenotype expression of the
gene, as it varies between each case, however
there is a similar correlation in the expression
within the same family
Autosomal Dominant Inheritance Table
Treatment
NF1
• Some NF1 tumors can become cancerous so
the best and most immediate solution that is
recommended is surgery to remove the
tumors before they can mastasize or cause
damage in another fashion
• As an alternative, other cancer treatment
options are also viable, such as chemotherapy
and radiation
Treatment
NF2
• In addition to the methods described for the
treatment of NF1, there are other treatment
options for NF2
• For NF2, and MRI will show the appearance of
the tumor and surgery is an option to remove
tumors and correct cataracts and retinal
abnormalities
• So early recognition is paramount in
prevention
Treatment
Schwannomatosis
• There is no treatment currently available for
Schwannomatosis but surgery is the best
option
• Genetic testing is also available for families
with histories of NF1 and NF2, but currently
there is no testing for Schwannomatosis
Current Research
• The position of the gene that predisposes an
individual for NF1 is located on chromosome 17
• the associated protein is called neurofibromin
and is primarily located in nerve cells
• it is part of the regulation of cell division in
neurons
• Neurofibromin is a tumor suppressor gene whose
function is to inhibit the p21 ras oncoprotein, so
if mutated, tumors will not be suppressed, which
is problematic
Current Research
• The NF2 gene is located in chromosome 22
and the product is a protein that is a tumor
suppressant protein called merlin or
schwannonim
• Merlin apparently regulates growth in specific
cells, Schwann cells and meningeal cells
Current Research
• When researchers can figure out the exact 3D
shape, something can be done in the production
of a drug or through an application of gene
therapy to remove, or repair the gene entirely
• Schwannomatosis is a product of a mutation on
chromosome 22 and 17
• Researchers are also trying to determine more
about what the protein Merlin controls within the
cell
Current Research
• In addition to the Merlin protein, researchers
are trying to determine more about the
protein neurofibromin and its association to
other genes and disabilities
• If a child does not have abnormal skin spots,
the goal in treatment is to prevent the
development of neurofibromas, or tumors
Current Research
• With regards to cancer research in preventing
tumors from developing and growing, more
efforts are being put into three categories
• Cytotoxics (cell poisons)
• Antihormonals (block hormone receptors)
• Adjuvants (drugs which supplement the
performance of the main drug)
Current Research
• As the Ras pathway is very intimately
associated with NF, a lot of research is being
put in to inhibit the biochemical pathway
• It is also important to figure out which Ras
protein pathway is affected by NF
Works Cited
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"Defining the Future of Neurofibromatosis Research." National Institute of
Neurological Disorders and Stroke (NINDS). Web. 28 Feb. 2011.
<http://www.ninds.nih.gov/news_and_events/proceedings/neurofibromatosis_wk
shp.htm>.
"Neurofibromatosis Information Page." National Institute of Neurological Disorders
and Stroke (NINDS). Web. 28 Feb. 2011.
<http://www.ninds.nih.gov/disorders/neurofibromatosis/neurofibromatosis.htm>.
"Neurofibromatosis." Wikipedia, the Free Encyclopedia. Web. 28 Feb. 2011.
<http://en.wikipedia.org/wiki/Neurofibromatosis>.
"Schwann Cell." Wikipedia, the Free Encyclopedia. Web. 28 Feb. 2011.
<http://en.wikipedia.org/wiki/Schwann_cell>.
"Schwannomatosis | Learn About NF." The Children's Tumor Foundation Neurofibromatosis, NF, NF1, NF2, Schwannomatosis. Web. 28 Feb. 2011.
<http://www.ctf.org/Living-with-NF/schwannomatosis.html>.
"Solubility Product Constants." Kemijsko-tehnološki Fakultet U Splitu. Web. 26 Feb.
2011. <http://www.ktf-split.hr/periodni/en/abc/kpt.html>.
Works Cited
• British Columbia Neurofibromatosis Foundation. Web. 27 Feb. 2011.
<http://www.bcnf.bc.ca/learn-more/nf-1/>.
• Chambers, :. Diana. "Neurofibromatosis-1: Treatment | Health32.Com."
Health32.Com | General Health Information Online. Web. 28 Feb. 2011.
<http://www.health32.com/neurofibromatosis-1-treatment-2/>.
• "Neurofibromatosis Type 1." Learn.Genetics™. Web. 28 Feb. 2011.
<http://learn.genetics.utah.edu/content/disorders/whataregd/nf1/>.
• "Figure 3 : Neurofibromatosis Type 1 [mdash] a Model for Nervous System
Tumour Formation? : Nature Reviews Cancer." Nature Publishing Group :
Science Journals, Jobs, and Information. Web. 28 Feb. 2011.
<http://www.nature.com/nrc/journal/v5/n7/fig_tab/nrc1653_F3.html>.
• British Columbia Neurofibromatosis Foundation. Web. 27 Feb. 2011.
<http://www.bcnf.bc.ca/learn-more/nf-1/>.
• "KICK Neurofibromatosis Print from Zazzle.com." Zazzle | Custom T-Shirts,
Personalized Gifts, Posters, Art, and More. Web. 28 Feb. 2011.
<http://www.zazzle.com/kick_neurofibromatosis_poster228922366357868822>.