When Should Family Members Get hATTR Genetic Testing?

Receiving a diagnosis of hereditary ATTR (hATTR) amyloidosis naturally brings up immediate concerns for your children and other relatives. Because hATTR amyloidosis is passed down in an autosomal dominant pattern—meaning each biological child of a person with a disease-causing mutation has a 50% chance of inheriting it—informing your family is an important step ^[1]. However, testing is generally reserved for adults. Medical guidelines recommend deferring predictive genetic testing for minors until they are at least 18 years old ^[2]. For adult relatives, testing should be done systematically through a process called cascade testing, but only after comprehensive discussion with a genetic counselor ^[1][2].

Testing Minors: Why We Usually Wait

Because hATTR amyloidosis is predominantly an adult-onset disease, children usually do not develop symptoms during childhood. Therefore, expert consensus guidelines generally recommend waiting until an at-risk individual is at least 18 years old to offer predictive genetic testing ^[2].

Deferring the test allows children to grow up without the psychological burden of carrying a genetic risk they cannot act upon during youth ^[3][2]. More importantly, waiting preserves their right to make their own informed choice as an adult.

Note: There are rare exceptions. If a child develops symptoms that could be related to amyloidosis, or if your family has a very rare, early-onset TTR variant (the specific mutation), they should undergo a diagnostic evaluation by a specialist regardless of age ^[1].

Cascade Testing for Adult Relatives

For adults in your family, the recommended approach is cascade testing ^[4]. This means offering targeted testing for your specific known familial variant to your closest biological relatives first—such as your parents, siblings, and adult children. If a relative tests positive, testing is then offered to their first-degree relatives ^[4]. (Spouses or partners do not need testing unless they have their own family history of the disease).

Testing should look specifically for the pathogenic (disease-causing) mutation already identified in your family. A relative who tests negative for this specific variant generally does not have the familial risk and does not require hATTR surveillance ^[1].

If an adult relative tests positive, they are considered to have an inherited genetic risk. It is crucial to understand that having the genetic mutation does not mean they have the disease, nor does it guarantee they will ever develop it ^[1][5]. The disease has variable penetrance (the likelihood of showing symptoms) and the age of onset can range widely depending on the specific TTR variant and individual factors ^[1][6][7].

A positive result means the relative should begin an individualized schedule of clinical monitoring (such as neurologic, cardiac, and autonomic assessments) tailored to the predicted age of onset for that specific variant ^[8][9][6]. This surveillance aims to catch any early signs of clinical disease so that doctors can evaluate them for disease-modifying therapies at the right time ^[4][10].

The Crucial Role of Genetic Counselors

At-risk family members should not rely on direct-to-consumer commercial DNA tests ^[2]. Instead, testing should be coordinated through a genetic counselor or a multidisciplinary amyloidosis center ^[1]. A genetic counselor will help your relatives navigate two major non-medical considerations before they decide to get tested:

• Insurance Considerations (U.S.): In the United States, a federal law called the Genetic Information Nondiscrimination Act (GINA) protects against genetic discrimination in health insurance and employment ^[11][12]. However, GINA does not cover life, disability, or long-term care insurance ^[11][12]. While some states offer additional protections, genetic counselors often discuss the importance of securing these insurance policies before a positive genetic test enters a person’s medical record ^[13]. This is a personal decision and should not delay urgent medical care for anyone experiencing symptoms.
• Emotional and Psychological Impact: Learning you are predisposed to a serious condition can cause significant anxiety and fear ^[3][10]. A genetic counselor provides a period of reflection before the test and ensures that psychosocial support is in place to help the individual handle whatever the results may show ^[2].