The following information may help to address your question:
How is hereditary amyloidosis inherited?
The hereditary amyloidoses are inherited in an autosomal dominant manner. This means that one altered copy of the disease-causing gene (called a mutation) in each cell is sufficient to cause the disease. The disease-causing mutation can be inherited from a parent or it can occur for the first time in an individual. Each child of an individual affected with hereditary amyloidosis has a 50% (1 in 2) risk to inherit the disease-causing mutation and a 50% chance of not inheriting the mutation. However, not all individuals with a mutation in a gene that causes hereditary amyloidosis will develop signs and symptoms of the disease.
Last updated: 9/16/2011
What are the signs and symptoms of familial transthyretin amyloidosis?
transthyretin amyloidosis (FTA) is a slowly progressing, adult-onset condition.
 Symptoms depend on which body parts are most affected. The age symptoms begin may also vary by country. In Portugal and Japan, people with FTA usually start developing symptoms in their late 20s to 40s. In other parts of the world, people with FTA may not have symptoms until after age 50.
The most common form of FTA affects the peripheral nervous system
. The peripheral nerves send messages from the brain and spinal cord to the rest of the body. Other forms of FTA can affect the brain, spinal cord, heart, and eyes.
Symptoms of FTA include
Weakness, numbness or pain in the lower legs and feet
• Carpal tunnel syndrome
in both wrists
• Sexual impotence
Urinary problems, protein
in the urine
Diarrhea or constipation
Unexplained weight loss
Dry eyes, increased pressure in the eyes (glaucoma)
, seeing ‘floaters
• Abnormal heart beat
, enlarged heart
Getting dizzy when moving from sitting to standing (orthostatic hypotension
Dry eyes and mouth
Later symptoms may include muscle weakness and stiffness, difficulty with coordination
, and congestive heart failure
Less common symptoms include skin changes, hearing loss
, shortness of breath, and anemia
Last updated: 11/15/2018
How is hereditary amyloidosis diagnosed?
In the case of hereditary amyloidoses, the existence of a family history
or similar illness is of great assistance in diagnosing the condition. However, not everyone with a mutation
in a gene
associated with hereditary amyloidosis will develop symptoms. Additionally, symptoms of the disease typically do not appear until older age and the condition may have been misdiagnosed in other affected family members. For these reasons, the absence of a family history may be misleading.
The diagnosis of amyloidosis is usually made by performing a tissue biopsy
and staining the tissue with Congo red stain to detect the presence or absence of amyloid deposits. The biopsy may be from any affected organ
, but biopsying the rectal mucosa
generally results in better detection of the following hereditary amyloidoses: transthyretin amyloidosis, apolipoprotein AI amyloidosis, fibrinogen Aα-chain amyloidosis (A Fib), and apolipoprotein AII amyloidosis (A ApoAII).
Additionally, when a hereditary amyloidoses is suspected, genetic testing
may be able to confirm a diagnosis. It is important to note that genetic testing may not be available for all types of hereditary amyloidoses. For those individuals interested in pursuing genetic testing, we recommend scheduling a genetics consultation
to determine whether genetic testing would be appropriate and available.
Last updated: 9/16/2011
How can I find a genetics professional in my area?
Last updated: 12/6/2017
We hope this information is helpful. We strongly recommend you discuss this information with your doctor. If you still have questions, please
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