# TTR Gene Screening Since the Advent of Biotherapies in France: A Nationwide Retrospective Survey Between 2018 and 2023

## TL;DR

This study shows a significant increase in TTR gene testing in France from 2018 to 2023, likely due to new biotherapies improving outcomes for hereditary transthyretin amyloidosis.

## Contribution

The study provides the first nationwide assessment of TTR gene screening trends in France following the introduction of biotherapies.

## Key findings

- There was a 108% annual increase in TTR gene sequencing from 2018 to 2023.
- 1,179 patients were diagnosed with pathogenic TTR variants during the study period.
- Positive test rates remained stable despite increased testing.

## Abstract

Hereditary transthyretin amyloidosis (ATTRv) is a rare genetic disorder caused by mutations in the TTR gene. Associated with various clinical phenotypes like polyneuropathy and cardiomyopathy, ATTRv has historically had poor outcomes. Recent advances in biotherapies have significantly improved these outcomes. This study aimed to assess the evolution in genetic TTR variant screening since the advent of biotherapies in France in 2018.

This nationwide retrospective study analyzed data and genetic results from patients who underwent TTR gene sequencing from 2018 to 2023.

16,640 patients were tested during the period studied. There was a 108% increase in the number of TTR gene sequencing performed annually between 2018 and 2023. Positive rates remained stable despite increased testing (7.09% over time). During this 6‐year period, 1,179 patients were diagnosed with a pathogenic variant of TTR.

The study shows a substantial rise in TTR genetic testing in France, likely linked to the deployment of biotherapies. These findings underscore the necessity of integrating TTR gene sequencing into standard diagnostic procedures, especially given the effectiveness of treatments and the stability of positive rates.