Which are the causes of Amyloidosis?

Amyloidosis is caused by the misfolding of proteins into abnormal, insoluble fibers called amyloid fibrils, which accumulate in various organs and disrupt their normal function.

The Mechanism of Misfolding

Think of proteins in your body like complex origami structures that must be folded perfectly to work. In Amyloidosis, these proteins lose their shape and clump together like tangled yarn. These clumps, or fibrils, deposit in tissues—such as the heart, kidneys, or nerves—eventually preventing these organs from functioning properly. The underlying trigger for this misfolding varies depending on the specific type of Amyloidosis.

Genetic and Metabolic Factors

Genetic factors play a central role in hereditary forms of the disease. For instance, mutations in the TTR gene can cause Transthyretin-related Amyloidosis, where the liver produces unstable proteins that misfold. In other cases, such as AL (light chain) Amyloidosis, the cause is metabolic; the bone marrow produces abnormal plasma cells that secrete faulty antibody proteins. Unlike hereditary forms, AL Amyloidosis is not passed down through families but is considered a clonal plasma cell disorder.

Distinguishing Causes and Risk Factors

In clinical research, we distinguish between a cause (the direct biological mechanism, like a genetic mutation) and a risk factor (a condition that increases the likelihood of the disease). For example, chronic inflammation or long-term infections can lead to AA Amyloidosis, where the body produces too much of a protein called Serum Amyloid A. While the inflammation is the driver, the specific susceptibility of an individual's protein folding process determines whether they will develop the condition.

Current Research

While we understand the basic mechanism of protein misfolding, research is actively investigating why certain individuals develop clinical symptoms while others with similar protein profiles do not. Scientists are currently using advanced imaging and proteomics to better understand the early stages of fibril formation, aiming to develop therapies that stabilize proteins before they can aggregate and cause damage.

Medical Disclaimer: This information is for educational purposes only and does not constitute medical advice. Please consult with a specialist physician or genetic counselor to discuss your specific clinical situation.

References

• NIH Genetic and Rare Diseases Information Center (GARD)


• Orphanet: The portal for rare diseases and orphan drugs


• Amyloidosis Foundation


• Online Mendelian Inheritance in Man (OMIM)