Cece, living with hATTR amyloidosis

hATTR Amyloidosis

Due to the gene variant in people with hATTR amyloidosis, the TTR protein, which is made primarily in the liver and carries vitamin A, can undergo a change from its normal function. The abnormal protein then accumulates throughout the body as amyloid fibrils—particularly in the heart, nerves, GI tract, and musculoskeletal tissues—causing debilitating symptoms.

hATTR amyloidosis is an autosomal dominant disease, meaning a person needs only one copy of the variant gene to manifest the disease. Therefore, it can be inherited from one parent. More than 120 different TTR gene variants have been identified to cause hATTR amyloidosis. Some variants are more common in certain populations, including those of Portuguese, Swedish, Japanese, African and Irish descent.

Symptoms Associated with hATTR Amyloidosis

hATTR amyloidosis symptoms can vary from person to person, depending on which organs or tissues are affected, and can worsen as the disease progresses.

Symptoms may include:
  • Numbness, pain and weakness in the limbs

  • Impaired balance and difficulty walking, and musculoskeletal manifestations, such as carpal tunnel syndrome and osteoarthritis

  • Alternating episodes of diarrhea, constipation, nausea, and vomiting

  • Cardiovascular issues, such as shortness of breath, conduction abnormalities and arrhythmias

For a more comprehensive list of symptoms, see the hATTR amyloidosis backgrounder below.

Learn More About hATTR Amyloidosis

Download the Alnylam hATTR amyloidosis Backgrounder.

This is one family’s story

“Amyloidosis has kind of been the black cloud over my family.” – Tonya, family living with hATTR amyloidosis

Know Your Family History

The Bridge®

The Bridge® is a program designed to help raise awareness of hereditary ATTR (hATTR) amyloidosis and promote education on the condition for patients and their families.

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Alnylam Act®

Alnylam Act® provides no-charge, independent genetic testing and counseling to individuals in the US and Canada who may have hATTR amyloidosis.

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