What is ATTR amyloidosis (ATTR)?
ATTR amyloidosis (ATTR) is an underdiagnosed disease with symptoms that can worsen over time and affect multiple parts of the body, including the heart, nerves, and digestive system.
What causes ATTR?
Transthyretin (TTR) is a protein made primarily in the liver that carries vitamin A and other substances throughout the body.
In ATTR, TTR proteins become toxic to the body by misfolding and taking on an abnormal shape.
This abnormal shape causes the protein to build up over time in various parts of the body, including the heart, nerves, and digestive system. The buildup of abnormal proteins is called amyloid deposits.
Amyloid deposits damage parts of the body, causing symptoms of ATTR.
Are there different types of ATTR?
There are 2 types of ATTR, wild-type ATTR (wtATTR) and hereditary ATTR (hATTR).
- wtATTR is not inherited and may be associated with aging
- hATTR is caused by an inherited gene variant, or change, in the TTR gene passed down through family members. The gene variant causes the TTR protein to misfold and build up in the body as amyloid deposits
While either type of ATTR can manifest in a variety of ways, wtATTR is more commonly associated with heart‑related (cardiac) symptoms, and hATTR is more commonly associated with heart-related and/or nerve‑related (polyneuropathy) symptoms. ATTR with heart-related symptoms may be referred to as ATTR-CM (ATTR with cardiomyopathy) and ATTR with nerve-related symptoms as ATTR‑PN (ATTR with polyneuropathy).
