**Author Listing - Lead/ Submitting Author (we will be communicating with this individual): Name, Institution, City and State where the work was done. Co-authors will be added in a separate section.**
Miguel Aibar Arregui. Department of Internal Medicine, Hospital Clínico Universitario Lozano Blesa, Zaragoza, Spain

**Main Body of the Abstract**
The study of the circulating transcriptome provides a snapshot of the molecular processes occurring in an individual at a given time using minimally invasive approaches. Consequently, the analysis of gene expression profiles in patients with ATTR amyloidosis potentially allows us, not only to investigate the molecular mechanisms underlying the etiopathogenesis of the disease, but also to identify potential diagnostic biomarkers. To date, the number of studies investigating gene expression profiling in cardiac TTR amyloidosis is limited. This is particularly notable in the study of small RNAs expression profiles, where only targeted approaches have been applied. Here, by using high throughput RNA sequencing methods, we have generated the transcriptional profile of both cell-free RNA in plasma and circulating RNAs carried into extracellular vesicles (EV) from patients with cardiac ATTR-wt (n=20), and ATTR-v (n=20) amyloidosis. Differential miRNA and gene expression analyses were performed comparing the ATTR amyloidosis groups with patients with cardiac involvement other than amyloidosis (n=20) and healthy volunteers (n=20). Additional functional enrichment analyses of both RNA species were carried out using Gene Ontology. While differential gene expression of protein coding genes was limited to EV-carried RNAs, changes in miRNAs expression were found in both cell-free and EV-carried RNAs. Moreover, 88 miRNAs were found differentially expressed in ATTR by both approaches. Importantly, some miRNAs were differentially expressed in both ATTR-wt and ATTR-v amyloidosis, being potential biomarkers currently under study. Interestingly, the pathways related to histone modifications and those associated to protein catabolism by the proteasome were enriched in all the comparisons.



Circulating transcriptome profiling in cardiac TTR amyloidosis by genome-wide analysis. PB15 (#376)

We invite you to attend the XIX International Symposium on Amyloidosis to be held in Rochester, MN.

This symposium is organized as a hybrid meeting (with the focus on in-person) held from Sunday, May 26 through Thursday, May 30, 2024.

Together with the ISA Board and members of Mayo Clinic, a very attractive scientific hybrid program is being planned. The program will cover a variety of types of systemic amyloidosis: ATTR (hereditary and wild-type), AL (light-chain), AA and less frequent forms. There will be key lectures, specific symposia including those company sponsored, oral presentations and poster sessions of accepted abstracts.

COURSE DESCRIPTION
This program will provide a comprehensive review of state-of-the-art education in systemic amyloidosis: basic science, pathophysiology, diagnosis, current and emerging treatments. Scientific presentations will include competitive oral and poster abstracts. The rapid evolution of scientific discovery and expanding treatment options has created tremendous interest in the field and this meeting will fill and important gap in educating scientists and clinicians.