Is AL Amyloidosis Genetic or Hereditary? Explained

It is completely understandable to worry about your children’s health after an amyloidosis diagnosis. However, if your condition has been definitively confirmed as AL amyloidosis, you did not pass this disease to them, and they do not need genetic screening for it ^[1][2].

Is AL Amyloidosis Inherited?

AL amyloidosis is generally not inherited ^[3]. Instead, it is an acquired condition. This means it develops when acquired genetic changes arise in a small clone of white blood cells (plasma cells) in your bone marrow over the course of your lifetime ^[1]. These specific cells begin producing misfolded proteins called light chains ^[1]. Because these changes occur only in the affected plasma cells and are not present in your reproductive DNA (egg or sperm), they are not passed on to your children ^[3].

While some studies have found minor genetic variations that might slightly influence a person’s general susceptibility to plasma cell disorders, these are population-level findings ^[4]. They are not direct causes of the disease and are not reasons to genetically screen family members ^[4].

Why the Confusion? The ATTR Difference

It is very common for patients and families to worry about genetics when they hear the word “amyloidosis.” This is because a completely different subtype of the disease—hereditary ATTR amyloidosis (hATTR or ATTRv)—is passed down through families ^[5].

Hereditary ATTR is caused by a specific inherited mutation in the TTR gene ^[5]. It is inherited in an autosomal dominant pattern, meaning each child has an independent 50% chance of inheriting the gene if a parent has it ^[5]. For patients with ATTRv, genetic counseling and targeted testing for adult family members are important parts of managing the disease ^[6]. (Note that there is also a non-hereditary form of ATTR, called wild-type ATTR, which is related to aging and is not passed to children.)

AL amyloidosis is biologically different from hereditary ATTR, and the two conditions require entirely different testing and treatment approaches ^[3][2].

The Importance of Accurate Typing

Because hereditary ATTR amyloidosis is inherited and AL amyloidosis is not, being absolutely certain about your exact type of amyloidosis is vital for your treatment and your family’s peace of mind ^[7].

Sometimes, clinical symptoms can overlap. Both AL and ATTR amyloidosis can cause severe cardiomyopathy (disease of the heart muscle) or neuropathy (nerve damage) ^[8][9]. Furthermore, it is possible for a person to have a monoclonal protein—an abnormal antibody produced by a plasma-cell clone—while actually having hereditary ATTR ^[10]. A monoclonal protein does not always mean you have AL amyloidosis; it can coexist with other conditions and generally requires its own medical evaluation ^[10].

To ensure the correct diagnosis, your condition should be confirmed through amyloid protein typing ^[7]. The gold standard method is mass spectrometry, a laboratory technique that identifies exactly which protein is forming the amyloid deposits in your biopsy sample ^[11].

While mass spectrometry identifies the protein with high accuracy and strongly supports an AL diagnosis for that tissue sample, it is important to communicate with your doctor ^[11]. If you have an unusual family history of nerve or heart disease, or if your typing results were unclear, you should ask your specialist if genetic testing or a referral to a genetic counselor is appropriate to completely rule out an inherited condition ^[12][2].