Early Diagnosis of TTR Amyloidosis by Use of Molecular Biology

  • participants needed
  • sponsor
    Assistance Publique - Hôpitaux de Paris
Updated on 13 June 2021
Primary Contact
CHU Dupuytren (0.0 mi away) Contact
+10 other location
early detection
autosomal dominant
spinal cord
hereditary disease


Peripheral neuropathies are diseases that affect the nervous system outside the brain and spinal cord, their prevalence is 1% in the general population, the causes are extremely varied with more than 200 identified causes; the main ones are diabetes, excessive alcohol consumption and chemotherapy. They may be sometimes disabling but generally preserve autonomy.

Transthyretin amyloidosis is a rare multisystematic hereditary disease with autosomal dominant transmission. They present usually as a peripheral neuropathies (FAP). They are due to a point mutation of the transthyretin gene (chr 18q). FAP is secondary to endoneurial amyloid deposits and are characterized by a slowly progressive sensory, motor and autonomic. FAP is the most severe hereditary polyneuropathy of the adult are irreversible and fatal within 5 to 12 years from onset.

Most frequent mutation of TTR gene is located on the second exon; but more than 100 mutations have been reported.

Prevalence of FAP is 1 per 1 million inhabitants. They have been reported until 1990s' in four endemic areas North of Portugal, Sweden, Japan and Majorca. In these areas, diagnosis is facilitated because of the stereotypical presentation : a length-dependent polyneuropathy with predominant involvement of thermal and pain sensations and autonomic dysfunction, early onset in the third decade and a predominant Met30 TTR mutation. Positive family history is frequent 85% (one of the parents is affected). Diagnosis requires detection of TTR mutation by molecular biology (blood sample) and characterization of amyloid deposit on labial salivary gland biopsy.


Study of the TTR gene by complete sequencing; search for amyloidogenic mutations of the TTR gene (according to the site http: // amyloidosismutations.com / mut-attr.php) in the laboratory of molecular biology of the CHU BICTRE (APHP) managed by Pr Anne Mantel.

Preselection of the cases to be tested among the cases of peripheral neuropathies of indetermined cause referred via the network Cornamyl of which the reference centers of the neuromuscular diseases are belonging .

Currently, FAP is a worldwide disease. Diagnosis of TTR-FAP is extremely difficult and usually delayed by 4 years in non endemic areas for many reasons :

  • positive family history are lacking in 50% of cases (sporadic forms).
  • incomplete ability of biopsies to characterize amyloid deposits.
  • clinical presentation is varied and may mimick many types of rare peripheral neuropathies: CIDP, axonal idiopathic polyneuropathy, upper limb neuropathies, recurrent carpal tunnel syndrome after surgery, ataxic neuropathy, motor neuropathy.

Conversely to endemic areas, look for V30M mutation is not enough to exclude TTR-FAP, TTR gene sequencing is required.

With the help of the french network for FAP (Cornamyl), cases have been identified in 81/100 geographical departments, with a wide genetic heterogeneity (41 mutations reported) ; age of onset is late: 75% after 50 yo.

Condition Polyneuropathy, Peripheral Neuropathy, Diagnosis, Differential diagnostic aspects, Idiopathic Progressive Neuropathy
Clinical Study IdentifierNCT03373370
SponsorAssistance Publique - Hôpitaux de Paris
Last Modified on13 June 2021

Similar trials to consider


Browse trials for

Not finding what you're looking for?

Every year hundreds of thousands of volunteers step forward to participate in research. Sign up as a volunteer and receive email notifications when clinical trials are posted in the medical category of interest to you.

Sign up as volunteer

user name

Added by • 



Reply by • Private

Lorem ipsum dolor sit amet consectetur, adipisicing elit. Ipsa vel nobis alias. Quae eveniet velit voluptate quo doloribus maxime et dicta in sequi, corporis quod. Ea, dolor eius? Dolore, vel!

  The passcode will expire in None.

No annotations made yet

Add a private note
  • abc Select a piece of text from the left.
  • Add notes visible only to you.
  • Send it to people through a passcode protected link.
Add a private note