Amyloidosis, hereditary, transthyretin-related

Inheritance

How is hereditary transthyretin amyloidosis inherited?

Hereditary transthyretin amyloidosis is inherited in an autosomal dominant manner. This is one way a disorder or trait can be passed down through a family. The first word, "autosomal," means on a chromosome that both males and females carry. Therefore, hereditary transthyretin amyloidosis can affect either males or females. The second word, "dominant," means a change in one copy of a person's TTR gene is enough for them to develop the disorder. We have two copies of every gene - one from our mother and one from our father - for a dominant condition, only one of them needs to have the problem. This means that if a parent carries TTR gene change (or mutation), they have a 50% chance to pass the gene mutation to each of their offspring, regardless of gender. This also means that there is a 50% chance that an affected parent would not pass the gene mutation on to their children. No parent has control over which genes they pass/don't pass to their children.

Genetic testing is available to determine if someone has inherited a TTR gene mutation. If you have a family member with hereditary transthyretin amyloidosis and you would like to know if you are a carrier, talk to your doctor or seek a referral to speak to a genetic counselor to discuss genetic testing in more detail. In the U.S., you can find a genetic counselor near you by searching on the Find a Genetic Counselor website (from the National Society of Genetic Counselors) at http://www.nsgc.org/findageneticcounselor.

References
Show More Content Like This

More Inheritance Content

How likely is hereditary transthyretin amyloidosis to be passed on in a family?

What does it mean to have a "variant" or "variant of unknown significance" in the hereditary transthyretin amyloidosis gene?

How likely is hereditary transthyretin amyloidosis to be passed on in a family?

We each get two copies of most of our genes from our parents. One copy comes from our mother and the other copy comes from our father. A person who has hereditary transthyretin amyloidsosis passes the gene change (or mutation) on to sons or daughters in an autosomal dominant manner. This means a son or daughter only needs one TTR gene mutation to have the condition. So, someone with hereditary transthyretin amyloidosis has a 50/50 chance passing on the gene mutation to a child, and a 50/50 chance to not pass it on. Most people with hereditary transthyretin amyloidosis inherit it from a parent. No parent has control over which genes they pass/don't pass to their children.

Other times, people who have hereditary transthyretin amyloidosis are the first person in the family with the disorder. This occurs because of a de novo mutation, which means that the TTR gene mutation happened randomly, most likely at the time of conception. In families with a child with a de novo mutation, the likelihood of having another child with hereditary transthyretin amyloidosis is extremely low. A de novo mutation in the TTR gene is an extremely rare occurrence, but can happen.

If you have a family member with hATTR amyloidosis or you would like to learn more about the genetics of the disorder, talk to your doctor or seek a referral to speak to a genetic counselor. In the U.S., you can find a genetic counselor near you by searching on the Find a Genetic Counselor website (from the National Society of Genetic Counselors) at http://www.nsgc.org/findageneticcounselor.

References
  • Transthyretin Amyloidosis. Genetics Home Reference website. Retrieved September 26, 2017 from https://ghr.nlm.nih.gov/condition/transthyretin-amyloidosis
  • Sekigima Y, Yoshida K, Tokuda T. Familial Transthyretin Amyloidosis. GeneReviews website. Retrieved September 26, 2017 from https://www.ncbi.nlm.nih.gov/books/NBK1194/
  • Obici L, Kuks JB, Buades J, et al. Recommendations for presymptomatic genetic testing and management of individuals at risk for hereditary transthyretin amyloidosis. Curr Opin Neurol. 2016;29 Suppl 1:S27-35.
What does it mean to have a "variant" or "variant of unknown significance" in the hereditary transthyretin amyloidosis gene?

Hereditary transthyretin amyloidosis is caused by changes (such as mutations) in the TTR gene. Several mutations have been described in this gene. Most of these cause some form of hereditary transthyretin amyloidosis. In rare instances, other changes in this gene do not necessarily cause disease, or it is not yet known if they do. These are called variants or variants of unknown significance (VUS) in a gene. If a variant is known to cause a disorder, it is known as a pathogenic or disease-causing variant. However, sometimes scientists are unsure what a variant means yet, because it has not been found before or has only been found in a few people. If you have a variant or VUS in the TTR gene, talk to your doctor about further genetic testing that may help you learn more. A genetic counselor may also be able to help you review your test results. In the U.S., you can find a genetic counselor near you by searching on the Find a Genetic Counselor website (from the National Society of Genetic Counselors) at http://www.nsgc.org/findageneticcounselor.

References

We use cookies to ensure that we give you the best experience on our website. By continuing to browse this site, you are agreeing to our use of cookies.

Continue Find out more about our use of cookies and similar technology

This content comes from a hidden element on this page.

The inline option preserves bound JavaScript events and changes, and it puts the content back where it came from when it is closed.

Remember Me